I've noticed what I can only assume is a bug with the advanced search:
The "search order" dropdown has an option to search "most recent topics first".
Anytime I use this with the default "message age" range of 0 to 9999, I very rarely get results from the most recent time period, unless I adjust the message age to something that will filter out posts from 10 years ago.
Here's an example:
Go to advanced search.
Type "attacking bombers" (without the quotes) in the "Search for" field.
Leave all other settings at the defaults, but choose "search most recent topics first".
Hit the search button and note that the first result is from November 25, 1999. Also note that in the 4 pages of results, most all are from 9+ years ago.
I've found some ways to work around issues like this, but it makes searching the forum pretty tricky.