Thank you for the response, but that option is in the Advanced section. Unfortunately, there is no option to limit Advanced searches to the current thread. I just tried searching for 'walkthrough' that way. It returned 20 results from the last 2 1/2 hours. Not a helpful way to find something.
It is ridiculous! The option to search the current thread is in the default search, but not in the advanced search. While the option to sort by date, or set a start date is in the advanced, but not the standard.
ARGHH!
Okay, so how does someone raise such a problem with the people who control this site? I can't seem to figure out how to contact them.