You can help to get rid of your dogs bad breath by using some dog toothpaste and brushing your dogs teeth with the dog toothpaste at least every 3 days.
Never use human toothpaste though on a dog because most if not all human toothpaste contains fluoride which is deadly poisonous to a dog.
They also make some dog treats that help clean and freshen your dogs teeth and breath when they chew and eat on the dog treats.
Another alternative if you can afford to do it is take your dog to the vet and have them do a through cleaning of your dogs gums and teeth which will help get rid of your dogs bad breath.