The exchange search engine is broken. Be sure to specify what type of item you are looking for, or use some other filter. If you use all, all, all - you won't always see everything.
STO Forum member since before February 2010.
STO Academy's excellent skill planner here: Link
I actually avoid success entirely. It doesn't get me what I want, and the consequences for failure are slim. -- markhawman
You just have to make sure you narrow down you're search as much as possible, and even then sometimes the exchange lags if there are a lot of people using it. The other night for example I sold over 500 duty officers no problems, then a bunch of people came on and it started lagging and not showing them right away, it's just one of those things.