Change target if target is fleeing

[krino 0]

Hey im fairly new to wrobot. and trying my best to search to forums for answers and learn, however i cant seem to figure this out.

I want to change target if my current target is fleeing, and there is another viable target that aint fleeing. Would that be possible?

ive tried to disable movement for x seconds, but its fixated on the same target and ignores the other mobs until the target comes back into range.
ive tried to decrease the "search units radius" without succes.
ive tried to spam a change target macro, when target aint targetting me. but it keeps changing the target back.

I know it seems like noobish fixes. but as i said im quite new, and ive tried to my best experience. 

Im hoping some of you with more knoweldge can help me out, and thanks in advance!