Puppy itchy but no fleas/ticks, any advice on how to help him?

Our puppy is almost 10 weeks old on Monday. Vet checked him for fleas or ticks and he has none. Vet said it’s just normal itchy skin on dogs. I’m giving him salmon oil in his food, as well as puppy vitamins, and probiotics, but wanted to know if anyone recommends any other product for dogs with itchy skin? I have been looking up these powders that help with these issues (to be applied topically) but the reviews were mixed. Any advice is appreciated 🙏😊