From what I gather, the forum requires you to create "tags" when creating a post. This is the only way for threads to show up when you search. Don't blame the site or the mods for people not taking the time o read the bright red text telling them this fact. Not tying to be an a$$ here, just saying.
As well, I agree win the comment on active topics. That's the page I have bookmarked. It's where I browse. There ARE often 2-3 posts o the same topic and even with VERY similar titles.
Never tried searching via Google, but I've seen multiple people swear by it, so it can't be bad!
If you can't find what you're looking for through either search method, or by quickly scanning active topics, make mention of that in your post. I'm guilty of reminding people to search first, but I don't say anything if they mention that they've tried. Can't say that for EVERYONE that has issue with multiple threads on the same subject, but that's how I roll. You can even lie to me and say you searched. Regardless of whether you did or not, if I have an answer or know of a thread that could help, I'll point you in the right direction.