The first thing to remember is to NOT rub the bedsore, especially if they are over a bony area. Make sure you take any pressure off the affected area. If the sore is ulcerated, make sure you reinse it well with normal saline or sterile water. Then clean with a betadine gauze pad.
I would recommend going to the doctor to see if the sore is infected and maybe have a culture taken from it to make sure there are no germs growing inside and maybe have an antibiotic prescribed. You could also cover the sore with an occlusive dressing which can be very helpful in helping fresh skin cells migrate.
Watch the ones that don't seem to be healing. You might want to look into further medical advice for those. Good luck.