Mother Dog/Milk Question Please Read?

do you know anything we could give Dixie (my Labrador) to make her produce more milk? Cause I took her to the vet before she had the puppies,and the vet said to keep her on normal feeding schedule.So I did that,but she doesn't have a lot of milk,so I am asking should I put her on puppy food for awhile?And also I took my dog to the vet,and got her checked out BEFORE I bred her,and the vet said all is good.Her hips are excellent and her elbows are excellent!She's up to date on everything!!