Now I understand why the rule book has a drawing for level flight.

Being serious - let me shed light on how a search works since this is what I do to pay for my toy airplanes.
There are three basic logic's that are used in a search as simple as ours - "And", "Or" and "Phrase".
"And" means that all of the words in the search must appear somewhere in the document.
"Or" means any of the words in the search must appear and
"Phrase" means that the exact phrase in quotes must appear.
I can't say for sure but it appears our search only supports "And" and "Phrase". You can use single characters in a "Phrase" like "I am a PAMPA member" but think of the list you would get if you used them in an "And" search! I am supersized that they allow 2 characters outside quotes.
Hope this helps.
Ken
One more thing - the string you are looking for does not have to be a word, it can be part of a word. If you just searched for "os" for example, every word in the forum that has "os" it will show. Boss, Gloss, Oscar, posterior - you get the drift.