how to get drywall dust out of screens

We are talking about window screens, right? Just making sure.

I would first try to vacuum with a brush attachment, making sure the suction comes from indoors side of the screen (i.e. the side that the dust particles were coming from). I'd be honest though, after you power washed it, I don't know if that's going to work.

Is it the gypsum (white) particles or the paper fibers (brownish) that are visible most? If it looks white and the screen is vinyl, I might have tried to dissolve (or just soften) the gypsum with vinegar or citric acid, then power wash again.