I used a string of 3 words in the post itsme gave above, and found the thread quite quickly as someone had posted the identical email. Still, I find the search function on FT frustrating. I have never found a way of using Boolean logic. I'm accustomed to searches elsewhere where I can define that words have to be present sequentially, or within a couple words of each other, or both in the same post.... I've tried various Boolean operators on FT without much success.
For FT, I go to advanced search. Then I use a keyword. If I expect it to be in the title, I only search there. If I expect it to be in the body, I search there. If I'm fortunate enough to remember a poster in the thread, I use that as a search criteria. For this search, I knew it would be a fairly recent post. Thus, I put a time constraint on it.
Having said that, search is still very erratic at returning a post. I might know very specifically both a term used and the poster, yet have great trouble in finding the post.