In google type your search word or words. Then <space> site:http://mwomercs.com/forums/forum/94-guides-strategies/
or whatever sub-forum you want to search. Just go to the forum you want, copy the url and paste it into the google search bar after site:
<search words> site:<url of forum>
Edited by Krazy Kat, 20 September 2013 - 04:36 PM.