Using the Google method you mention is the best way to search this site and its companion site, iRV2.com.
On iRV2.com they give you a search box that does the same thing as the Google search, but I don't see one here.
Remember, if you use Google to search on iRV2.com, put the term "f101" in the Google query, if you want to search just the Winnebago Owners Forum, e.g.,
"Adventurer" "BIM" "f101" site:irv2.com
2008 Holiday Rambler Admiral 30PDD (Ford F-53 chassis)
2009 Honda Fit Sport