Connecting to Folder but filtering by file name

Hello,

We are conecting to a folder which has multiple files -- basically 3 different file formats.  Is there a way when we connect to the folder -- maybe going into 'Advanced' where it shows it in M code -- and filtering by specific file names?  i.e. We have file names "Positions", "Transactions" and "Returns" all in the same folder.  Only want to view where file names begin with 'Position' or end with .xls -- like filtering positions* or *.xls.

Thanks!

Dan