Exercise choices to target muscle

I’m a bit confuse about the traps training, I read the Jim stoppanis book, and It’s written there what exercises should do for any training split like 3 day training split, but for the traps exercise is not written there what u should do for training split, I read there that all rowing exercises also hit the middle traps, is that mean that I don’t need to include other exercises for middle traps if I already do the rowing exercises for my back, and some article says that pull ups and pull down also hit the lower traps, is that also mean that I don’t need to include other exercises for lower traps if I already do the pull ups and pull down, just the shrugging, and is the rowing also hit the lower traps if yes I don’t need to include exercise for lower traps? and if the rowing exercise also target the middle traps, and for example I do 2 rowing exercises, should I need to do 2 exercises for upper traps and lower traps, or I’m gonna do 8 sets for upper traps and 8 sets for lower, (not reps) because I do 2 rowing exercise, each exercise is 4 set, so the total set of 2 exercises is 8, please define all of this…

Thank You!

This Video Might help with knowing which areas of the traps are hit when training. http://www.workouttrainer.com/home/videos/workout-0shoulder-shrugs