Not really, maybe a few here and there, but Du do have to consider that there is generally a basic structure to all faces. While everybody is different there are still many similarities in proportions and what not.
They all have the same head structure. The lips not really, nose kinda, eyes not really but they're positioned very similarly. Tips: Change the head structure (make Mehr shorter faces), Bewegen the eyes farther apart oder lower it, and have Mehr variation with noses. I drew some really quick bad faces. It can give Du an idea, but these faces aren't the best either.
They appear similar at a quick glance but when Du really look at them they are all different and look unique theres actually a significant amount of differences in each one of them. However me being me I am far too lazy to go over each and every difference XD
The general facial structure seems to be relatively the same, but other than that, there are other variations that make them Mehr unique.
Try basing your drawings off of Fotos from real faces to learn Mehr about proportions and differences in facial features. You'll find that it helps Du a lot.