How to display domain validations and errors in a partial view modal bootstrap?

I'm using DDD and I have some validations in my domain that need to be done, however when I use ModelState.AddModelError and return my model and my PartialView, the form of my Partial does not remain in modal open. Instead, it displays an html page without css styles. I know I have to do with Javascript / Ajax / jQuery and return a Json on the Controller. But I still have not gotten it right. Any effective way to do it?

I put the codes to make it easier to see something that is wrong. Basically what I want is to return the errors that happen in the controller to be displayed inside the PartialView loaded in bootstrap modal.

Controller code

public ActionResult Create()
        {
            ViewBag.Title = "Adicionar Ação de Formulário";
            return PartialView("~/Views/Acao/_AcaoFormulario.cshtml", _acaoAppService.Iniciar());
        }

        [HttpPost]
        public JsonResult Create(AcaoViewModel acaoViewModel)
        {
            JsonResult result;

            var errorResult = new List<ValidationError>();

            if (ModelState.IsValid)
            {
                var acaoReturn = _acaoAppService.Salvar(acaoViewModel, acaoViewModel.AcaoId);

                if (!acaoReturn.ValidationResult.IsValid)
                {

                    foreach (var error in acaoReturn.ValidationResult.Erros)
                    {
                        errorResult.Add(new ValidationError(error.Message));
                    }

                    return result = Json(new ActionResponse(false, errorResult), JsonRequestBehavior.AllowGet);
                }

                return result = Json(new ActionResponse(true, null), JsonRequestBehavior.AllowGet);
            }

            errorResult.Add(new ValidationError("Ação Inválida"));

            return result = Json(new ActionResponse(false, errorResult));
        }

PartialView with Modal Loaded Form

@model PAD.Application.ViewModels.AcaoViewModel

@{
    Layout = null;
}

<div class="modal-dialog modal-lg">
    <div class="modal-content">
        @using (Html.BeginForm(null, null, FormMethod.Post, new { id = "acaoFrm", onsubmit = "acaoSubmit()" }))
        {
            <div class="card-header">
                <button class="close" type="button" data-dismiss="modal">
                    <span class="sr-only">Close</span>
                    <span aria-hidden="true">x</span>
                </button>
                <h4 class="card-title">@ViewBag.Title</h4>
            </div>
            <div class="modal-body">
                <div class="card-block">

                    @Html.AntiForgeryToken()
                    @Html.HiddenFor(model => model.AcaoId)

                    <div class="text-danger">
                        <ul></ul>
                    </div>

                    <div class="form-body">
                        <div class="row">
                            <div class="form-group col-md-4">
                                @Html.LabelFor(model => model.Nome)
                                @Html.TextBoxFor(model => model.Nome, htmlAttributes: new { @class = "form-control" })
                            </div>
                            <div class="form-group col-md-4">
                                @Html.LabelFor(model => model.Tipo, htmlAttributes: new { @for = "tipo" })
                                @*@Html.TextBoxFor(model => model.Tipo, htmlAttributes: new { @class = "form-control" })*@
                                <select class="form-control" id="tipo" name="tipo">
                                    <option>-- Selecionar --</option>
                                    <option value="A">Ação BD</option>
                                    <option value="C">Consulta BD</option>
                                </select>
                            </div>
                            <div class="form-group col-md-4">
                                @Html.LabelFor(model => model.FonteDadosId)
                                @Html.DropDownListFor(model => model.FonteDadosId, Model.ComboFonteDados, "-- Selecionar --", new { @class = "form-control" })
                            </div>
                        </div>
                        <div class="row">
                            <div class="form-group col-md-4">
                                @Html.LabelFor(model => model.Take)
                                @Html.TextBoxFor(model => model.Take, htmlAttributes: new { @class = "form-control" })
                            </div>
                            <div class="form-group col-md-4">
                                @Html.LabelFor(model => model.Execucao, htmlAttributes: new { @for = "execucao" })
                                @*@Html.TextBoxFor(model => model.Execucao, htmlAttributes: new { @class = "form-control" })*@
                                <select class="form-control" id="execucao" name="execucao">
                                    <option>-- Selecionar --</option>
                                    <option value="E">Excluir</option>
                                    <option value="X">Executar</option>
                                    <option value="S">Salvar</option>
                                </select>
                            </div>
                            <div class="form-group col-md-4">
                                @Html.LabelFor(model => model.RotinaId)
                                @Html.DropDownListFor(model => model.RotinaId, Model.ComboRotinas, "-- Selecionar -- ", new { @class = "form-control" })
                            </div>
                        </div>
                        <div class="row">
                            <div class="form-group col-md-6">
                                @Html.LabelFor(model => model.Descricao)
                                @Html.TextBoxFor(model => model.Descricao, htmlAttributes: new { @class = "form-control" })
                            </div>
                            <div class="form-group col-md-6">
                                @Html.LabelFor(model => model.PopUpContainer)
                                @Html.TextBoxFor(model => model.PopUpContainer, htmlAttributes: new { @class = "form-control" })
                            </div>
                        </div>
                        <div class="row">
                            <div class="form-group col-md-6">
                                @Html.LabelFor(model => model.Where)
                                @Html.TextAreaFor(model => model.Where, htmlAttributes: new { @class = "form-control", @rows = "10" })
                            </div>
                            <div class="form-group col-md-6">
                                @Html.LabelFor(model => model.OrderBy)
                                @Html.TextAreaFor(model => model.OrderBy, htmlAttributes: new { @class = "form-control", @rows = "10" })
                            </div>
                        </div>
                    </div>
                </div>
            </div>
            <div class="card-footer">
                <button class="btn btn-danger shadow" type="button" data-dismiss="modal">
                    <span class="icon-remove"></span> Fechar
                </button>
                <button type="submit" class="btn btn-success shadow pull-right" onclick="document.getElementById('acaoFrm').submit();">
                    <span class="icon-check"></span> Salvar
                </button>
            </div>
        }
    </div>
</div>

Javascript calling modal

$("#novaAcao").click(function () {
        $("#modal").load("/acao/create", function () {
            $("#modal").modal("show");
        });
    });