what does $query contain? Best would be if you show us a complete script that demonstrates the problem you are having. I'd imagine you should only need half a dozen lines including print statements and initialisation to set variable values.

Update: using your "context":

use strict;
use warnings;

my $mystring = "This is a non-sense sentence.";
my $query    = "non-sense";

print $mystring =~/\b($query)\b/i ? "Matched" : "Missed";
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prints Matched as expected. Again, please supply a small script (like the one above) that demonstrates the problem.

Note that there are several flavours of hyphen depending on the character set you are using. Maybe the hyphens in the two strings are actually different characters?

If you want to find a substring inside a string, index might be a better choice than a regex (because you don't have to compile the regex, it's probably clearer to other people, and there's less unexpected side effects like metachars):

$string = "This is a non-SENSE sentence";
$substring = "non-sense";
print "Match!" if index(lc $string, lc $substring) >= 0;
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Thank you for your suggestions. It was an encoding problem which caused the Regexp not to work. Thank you also for the Index solution, it works very fine too

Some for context

$mystring="This is a non-sense sentence.";
$query="non-sense";
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