I think you are mixed up :-)

You should turn on strict and warnings

use strict;
use warnings;
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They will give you hints.
You split $_ but you are not setting it. You also say you want to find files that match, match what? There is no need to quote variables like you do, and you should check so that your opendir worked.

opendir THISDIR, $stuff or die "Noo $!";    #open the content director
+y
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