Trying to locate advice, social conversation, or anecdotal evidence on a particular topic? You can strategically search Google for that!

1. Perform a google search for your topic. 
2. On the results page, navigate to the search result url. 
3. Add the following to the immediate end of the url: &udm=18
4. Hit enter. All your results should now come from public forums.

Source: Reddit discussion where I originally found the search strategy.

Update: Google has recently added (back?) their forum filter, found in the same place under the search box on results pages.This filter performs the same function as the url extension listed above.