Hello, I have been working on a code for work and I found an odd glitch in my regular expression. I am looking through several blocks of texts for the Titles of some documents. The first title is "Screening Ligands by X-ray Crystallography." The text with that clearly has Screening Ligands by X-ray Crystallography in it. However, my regualr expression (below) does not pick it up. I have removed the 40 lines of code before this for brevities sake.

#!/usr/bin/perl
use warnings;
use strict;
use feature qw(say);

...
...

if ($text =~ /Screening Ligands by X ray Crystallography/) {
                        say "MATCH!";
                }
                else {
                        say "NOPE!";
                }
}

[download]
However, if I do the code below, I do get a match. 
if ($text =~ /Screening Ligands by/) {
                        say "MATCH!";
                }
                else {
                        say "NOPE!";
                }
}

[download]
I have narrowed down the issue to the "-" I think. However, I can't search for the titles without the "-" as maybe 2/3rds of them have it. Any thoughts on how to get around this?

EDIT: Based on what you all wrote, I began looking at a few of the others that were failing and have proven its not the "-" Its still not working correctly, but I at least know its not what I thought. I may even know what the issue is, but I'll need to run some tests. I think it may be an issue from the original titles not matching what's actually in the document.

In reply to Regular Expression Hiccup by Mindsword

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