I have a patch for searching perlvar with "perldoc -a"; see http://www.mail-archive.com/perl5-porters@perl.org/msg89839.html.

I'm also working on creating an index to the perl documentation for searching by keyword with "perldoc -k". See http://pod-indexing.annocpan.org. You can try the latest version of perldoc -k there, see for example http://pod-indexing.annocpan.org/perldoc-k.cgi?keyword=context.