Search in Email returns incomplete results iPhone

Im trying to figure out how to get iPhone email search to work reliably, relative to the capabilities of the gmail that it is attached to. When I search in email against a gmail source Ive found that I get the most results by searching for All, within email folder All Email, and by searching against the emails found on server. However, when doing a simple keyword search like this, I may get 5 results on iPhone, but 50 results when I search on the gmail website. To make matters worse, sometimes iPhone returns No results, where gmail returns 5 or 10. This makes it very difficult to determine if Ive just misspelled someones name, or the keyword in some simple way.
Is there a setting somewhere that would allow iPhone gmail search to return consistent find results to Gmail search, or should I just continue to use the website to search?
iPhone 3g iOS 4