use strict;
use warnings;

my @strings = qw{
   ac_dajhta_theWord
   sd_dfdfe_fdfdv
   ca_hereeds_theWord
   se_dcvdfdef_dsfd
   cx_hserj_theWord
   fa_dferefvdvv_fadfde};

my @matchingStrings = grep m{_theWord}, @strings;

print qq{$_\n} for @matchingStrings;

##</code><code>##

ac_dajhta_theWord
ca_hereeds_theWord
cx_hserj_theWord