The phrase typed into the search box has to match exactly: "pilot fog lights" must appear exactly that way for it to be found. It won't match "pilot fogs" or "pilot lights" or even "pilots".
Using AND "pilot AND lights" will match any post that has the word "pilot" and the word "lights" in it anywhere in it, not just the phrase "pilot lights". Doing so gave me several pages of results, many of them relevant. It even found this very thread.
This is different from, say, Google, which will automatically match plural works (pilot and pilots will match if you enter pilot), and it automatically "ANDs" words together. You have to explicitly say "pilot fog lights" in Google to match that exact phrase.
Unfortunately, unlike some sites, you can't point Google directly at 914world.com: 914world.com: pilot fog lights. This will give you only Classic threads (and probably not even all of those), not regular threads on the site. There's talk of fixing this on the site to Google can crawl the whole site, but it won't work right now.