Why does my dog get sick every few days? 10 days later, he died.

I may have bought a sick dog. It's best not to buy it from a vendor. I can go to a kennel or an individual breeder. They usually finish the vaccination when the dog is just full moon, and the incidence rate will be much lower. The puppy I just bought can't be bathed at once. I need to acclimate it at home for two weeks, and then take it to get vaccinated. You can't bathe it for a week after two or three vaccinations.