To get boogers out of your newborns nose, put pepper under their nostrils and it will make them sneeze it out.
Hand to God, this advice was given to me. In defence, the giver was a childless aunt who was well-intended and quite concerned about the baby having a cold and being stuffed up.
Here's the thing: newborn babies were, just days prior, in a liquid environment and there's a lot of junk to get out as well as getting the hang of breathing air (along with all the particulates in our modern world). So, a little stuffiness is not surprising.
If it really seems to be bug them and not just on-lookers, a few drops of breastmilk or infant saline solution (go to the drugstore, they'll take your money for this mild salt water solution) will help things along.