Snakes mites have a 30 day life cycle so if you don't get all the adults and every single egg....guess whose coming back to see you next month.
Know your enemy!
http://www.vpi.com/publications/the_...of_snake_mites
Get some Provent-A-Mite, the stuff most pet stores sell is pretty much a waste of your time and cash. (link was given to you in a Rich aka Spaniard's response this thread).
Mites are no joke. They are beyond irritating, not nice to deal with and are believed to be a vector for disease transmission. Best to get them knocked down and out completely. Remember Provent-A-Mite does NOT get sprayed directly on the snake. Read and follow the directions on the can to the letter.