This might be a little tricky but given a significant amount of programming time you could
have the software scan the contents of the text entered into the textbox,
examine any questions in the text string and automatically direct the user to the appropriate
thread where his question has already been answered.

I know that Google itself can't even pull that feat off just yet but it's worth a try.
Start off simple, like scanning for a question mark (?) and moving on from there.
Call the search routine "Dream~Scan". Once it's perfected you can license it out and make a mint.