Daedalus

Search engines don't have access to the non-public forums; i.e., the ones you need to be logged in to see.

It can be done. Let's say you want to search for Fiat in the Check In Bar & Residence, Soi 10 thread. First, go to that thread. Then left-click in the Search... tool at upper right, and select This Topic in the drop down menu. Next, type Fiat in the search tool, and hit enter. Et, voilà!