I would not stress too much.. 3 Pcs are not bad..
Sometimes when your snake sheds as they rub the shed skin can snag on stuff and break..
If your having complete sheds even 3 Pcs then sounds like your doing good.
Once in awhile you will get the full shed as long as it rolls right and doesnt snag on items in your tank.
If you are getting ant stuck shed then you will need to take a look at your Husbandry / Humidity.

Sounds great ! good luck with the rest