From my housebreaking tips:
Choose a command and spot you want it to use. The less accessible to strays,
the less chance of serious disease. If it is a female, choosing a
non grassy spot will avoid brown spots later. When you bring it home, take it
to the spot and give it the command in a firm, but friendly voice. Keep
repeating the command and let the puppy sniff around. If it does anything,
praise it. Really let it know what a good dog it is and how much you love it,
and maybe a treat. Note, being out there not only means you can praise it,
but it also keeps it from being snatched by a hawk. If it doesn't go, take it
inside and give it a drink and any meals scheduled. A young puppy will need to
go out immediately afterward. Go to the spot and follow the above routine.
Praising it if it goes is extremely important. If it doesn't go, take it back
inside and put it in its crate and try again soon. Do not let it loose in the
house until it does go.
Being out there and praising the 7 month old may make a big difference in getting him to go outside. Also run him around to stimulate the body and bring on the bowel movement.
Try adding generous amounts of canned pumpkin to their food. This will help 2 ways. It will help fill them up without adding calories, and make their stools distasteful. If the pumpkin doesn't work try grapefruit juice or one of the commercial additives, Forbid or Deter.
Obedience train them too. Sometimes it isn't an accident, but a control issue.
Having a good pack structure reduces such problems. The dogs see all the
people and dogs in the household as a pack with each having their own rank in
the pack and a top dog. Life is much easier if the 2 legged pack members
outrank the 4 legged ones. You can learn to play the role of top dog by
reading some books or going to a good obedience class. A good obedience class
or book is about you being top dog, not about rewarding standard commands with
a treat. Start at
http://www.dogsbestfriend.com/.