There are three commands, one each to search perldoc, cpan and perlmonks.org.
perldoc open
cpan LWP::Simple
monks unicode tutorial
perldoc command will usually take you directly to the perldoc page instead of showing you a list of results, whenever a perldoc page for what you type in exists.
Unless you have conflicting commands installed, you should be able to get away with just typing perl (or maybe even just pe) instead of perldoc.
Ubiquity rocks!