The Jargon File (version 4.4.7, 29 Dec 2003):

STFW
 imp., /S?T?F?W/

    [Usenet] Common abbreviation for ?Search The Fucking Web?, a suggestion
    that what you're asking for is a query better handled by a search engine
    than a human being. Usage is common and exactly parallel to both senses of
    RTFM. A politer equivalent is GIYF.


The Free On-line Dictionary of Computing (30 December 2018):

Search The Fucking Web
STFW

    (Always abbreviated STFW) A response implying that
   an inquirer could have easily found an answer to his question
   using Google or some other web search engine.  It
   is now often quicker and more productive to search the World-Wide
   Web than to RTFM.

   JFGI, GIYF and lmgtfy.com convey the same message.

   (2014-05-23)