How do I use the date range in Progress 4gl

I saw that you did there in the comment. But using functions that require the value of the table that you are searching for automatically turns the for each into a full table scan, that is, it will not be able to indices in your query. In banks with a large number of orders, this practice plays its performance in the garbage. I would do it this way:

FOR EACH ped-venda WHERE ped-venda.dt-emissao >= 02/01/2015 
     AND ped-venda.dt-emissao <= 02/28/2015 
 BREAK BY ped-venda.nome-abrev BY ped-venda.dt-emissao DESC:

Being the fixed date, as you suggested. This makes Progress use the most appropriate index, greatly speeding up the search result set of your query.