Fwiw, I've been here 8+ years, and in that time I can only remember using google a few times to search for something on the forum. The trick is just to key in on a fairly rare term used in a discussion, or to search for terms used by a particular user. For example, searching for "Chrysostom" is gonna bring up a boat load of links, but if you can search for something more specific like "Homily 12 on Philippians," things work fine. Of course, it takes time to get a feel for what/who to search for. And as PetertheAleut mentioned, tags are helpful in getting you pointed in the right direction.
Though now that I think about it, didn't Fr. Anastasios mention using Google as helping lessen the stress on the site? Ahh well, do as you find best