If this is inappropriate, please remove:

Is there a trick to using the search vehicles on this site? I have had little to no success. Case in point: I was in the NWA section of Airline Programs. I was looking to find out which coach fares can be ungraded using miles. No matter what I tried the best I would achieve was catching one word, such as "coach" or "miles" in the thread. I am sure there have to be many threads discussing upgrading with miles...........where are they and how do I find them?

Seriously, any help you can suggest for this and future searches would be appreciated. Can you use natural language, boolean logic, ..........Thanks !!!!!!!!