The first thing to keep in mind is that your puppy really isnt physically capable of holding their urine until they are about 12 weeks of age. By this time, the bladder and bowel muscles are more developed enabling them to gain control. However, most dogs will still have accidents until they are at least six months old when theyre better able to completely grasp the housetraining process.
Next, and perhaps most important of all, if you dont actually catch your dog in the act, then do not punish them or reprimand them in anyway. Even if only 30 seconds have passed, its too long for a puppy to remember and then associate being disciplined with the act of going in the house.
While the numerous books or training manuals on the subject of house training puppies are no doubt informative, they do lack the invaluable benefits of being able to see and hear the trainer.