How to put a layout for the search results of an input search that are within the echo?

I need to put a layout in the search results of the input search, I have a page that uses the layout of Cards of bootstrap 4, and I wanted the search results to look the same. This is the script I use in the layout of my other page:

<div class="container my-3">

    <div class="row">

        <?php foreach ($dadosUN as $UN): ?>

           <div class="col-12 col-md-6 col-lg-3 mb-3 mb-md-3">

                <div class="card">

                    <div class="img-container">

                      <a href="index.php?post=<?php echo $UN['title']?>"><img src="<?php echo $UN['capa']?>" alt="<?php echo $UN['alt']?>" class="card-img-top" id="imgUNcover"></a>

                    </div>

                    <div class="card-body">

                      <a href="index.php?post=<?php echo $UN['title']?>" class="card-title cardTitleLink"><h1 class="cardTitleUN"><?php echo $UN['title']?></h1></a>

                      <p class="card-text text-muted"><?php echo $UN['text']?></p>

                      <a href="index.php?post=<?php echo $UN['title']?>" class="btn btn-outline-danger btn-sm">Continue Lendo</a>

                    </div>

                </div>

           </div>

       <?php endforeach; ?>

    </div>

</div>

I was able to leave the search layout more or less similar using this script:

<div class="container my-3">

    <div class="row">

    <div class='col-12 col-md-6 col-lg-3 mb-3 mb-md-3'>  

        <?php

        if(isset($_POST['pesquisar'])&&!empty($_POST['cxnome']))
        {
        $nome=$_POST['cxnome'];
        $stmt = $conn->prepare("select * from bn_publicacao where title like :letra");
        $stmt->bindValue(':letra', '%'.$nome.'%', PDO::PARAM_STR);
        $stmt->execute();
        $resultados = $stmt->rowCount();

          if($resultados>=1){


            while($reg = $stmt->fetch(PDO::FETCH_OBJ)){

            echo "<div class='card'>";

            echo "<div class='img-container'>";

            echo "<a href='index.php?post='"; 

            echo $reg->title." ";

            echo ">";

            echo "<img src='";

            echo $reg->capa." ";

            echo "'";

            echo "alt='";

            echo $reg->alt." ";

            echo "'";

            echo "class='card-img-top'";

            echo "id='imgUNcover'";

            echo ">";

            echo "</a>";

            echo "</div>";

            echo "<div class='card-body'>";

            echo "<a href='index.php?post='"; 

            echo $reg->title." ";

            echo "class='card-title cardTitleLink'>";

            echo "<h1 class='cardTitleUN'>";

            echo $reg->title." ";

            echo "</h1>";

            echo "</a>";

            echo "<p class='card-text text-muted'>";

            echo $reg->text." ";

            echo "</p>";

            echo "<a href='index.php?post='";

            echo $reg->title." ";

            echo "class='btn btn-outline-danger btn-sm'>";

            echo "Continue Lendo";

            echo "</a>";

            }

          }else{
            echo "Não existe usuario cadastrado";
            }

          }else{
            echo "Preencha o campo de pesquisa";
          }
          ?>

          </div>

        </div>

      </div>

    </div>

</div>

More was bogged down, the layout only worked perfectly for the first result, the other cards stayed on top of each other, and the images looked different from the first card image:

Therightthingwouldbetostandsidebysidelikethisimage:

Can anyone help me?