Please use https://metacpan.org instead. It has been the de-facto module search engine used by the Perl community for the past 10 years at least. Only Google still seems to think that search.cpan.org is a thing.
At the next Perl Toolchain Summit (http://act.qa-hackathon.org/pts2018/) work will be done on metacpan.org, not on search.cpan.org. And this will also include work on the Perl 6 Toolchain, for that matter.
In your case: http://search.mcpan.org/search?query=X11-GUITest