Puppies have just been brought home.
Dogs that have never been outdoors are more likely to catch colds than dogs that are often outside. Puppies are more susceptible to illness than adult dogs.
Dogs must sleep in the yard, porch, under the stairs, car basement, floor. These are cold places that are easy to make dogs sick. Dogs kept in damp cages, urine and feces are not cleaned up also easily make dogs sick.
Dogs are bathed with cold water, or hot water, but not dried or not dried thoroughly.

Put your dog to sleep in a warm place, away from drafts.
Dogs should not be allowed to sleep on the floor (soil, marble, brick, etc.)
If you bathe your dog, you should put it in a closed room with a heater as possible. After bathing, dry the dog's hair thoroughly.
Feed more nutrients to create energy for the body to retain heat.
Dogs should be fully vaccinated against diseases to prevent viruses waiting to cause disease when the dog's resistance decreases.

Blogs

Dogs with colds: Recognition and timely treatment