You can use apropos to search names and descriptions inside man pages. For example:

    $ apropos timezone
    Date::Manip::DM5abbrevs (3pm) - A list of all timezone abbreviations
    dm_zdump (1p)        - timezone dumper
    Time::Zone (3pm)     - - miscellaneous timezone manipulations routines
    timezone (3)         - initialize time conversion information
    tzfile (5)           - timezone information
    tzselect (1)         - view timezones
    tzselect (8)         - select a timezone
    zdump (8)            - timezone dumper
    zic (8)              - timezone compiler

Can even search using regular expressions.