campaign - recon missions ????????

Hello to everyone,
Can someone please explain how to finish a recon mission? IT always says i failed to find the required objects.. But how do i know what i am looking for? There are no purple targets on the radar.
It doesnt say in the briefing.. I have flown around, and found many targets.. Why dont they count? Confused..
Also, it doesnt seem to matter what i do in the missions, the germans just keep coming! Does anybody have any advice on what the best missions are to help move the front line?
Thanks..
Can someone please explain how to finish a recon mission? IT always says i failed to find the required objects.. But how do i know what i am looking for? There are no purple targets on the radar.
It doesnt say in the briefing.. I have flown around, and found many targets.. Why dont they count? Confused..
Also, it doesnt seem to matter what i do in the missions, the germans just keep coming! Does anybody have any advice on what the best missions are to help move the front line?
Thanks..