As far as I understand, it is extremely difficult to successfully raise baby mice (whether from a pet or wild mouse) if the babys’ eyes aren’t open yet. They require frequent feedings and stimulation to the point that you will get very little sleep. Even with that, the chances of them surviving are still low. If the eyes are open, they will still need nutrients via a milk supplement (the ones for puppies are quite good for them), but they should be beginning to eat solid food on their own and have a higher chance of survival.
I don’t have any experience with this personally, but here’s some handy sites:
Rat & Mouse Gazette: Caring for Orphaned Baby Rats or Mice
AFRMA: Caring for Orphans
The Fun Mouse: Caring for Orphaned Mice