what if the car has more miles than seller claims

Does the paperwork list the mileage at time of purchase?

You should have signed the federal odometer statement... look and see how the mileage is listed on thst... if it is the same as your odometer, you can't do much... if it was falsified, you may be able to do something if it is really close to when you bought the car.. if it has been a while and there is the possibilitiy that you have put on those miles, that teamed with your having signed the statement will make it tough...