Individual words need to be 4 letters or longer, you won't get a hit on two 3 letter words. Use "+" for words to include and "*" for wildcard searches. Most of all it comes with remembering odd words in a thread, thinking laterally or mastering the Z4-Forum vernacular :wink:
Pretty much any well designed forums that don't have the finances for something like a Google Search Appliance will have the same issues.
I know what you mean about the "Use a search" response, just mention that you've tried when posting and if they come up scan over them! At the same time I do appreciate that some members answer the same questions a dozen times.