Nhận diện dấu hiệu có chấy. Kiểm tra tình trạng lây chấy của mọi người trong nhà. Thay quần áo sạch. Giặt sạch các vật dụng trong nhà mà đã được người có chấy sử dụng. Cùng lúc trị chấy cho mọi người trong nhà.

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
Many things can cause an itchy scalp, and it’s easy to mistake conditions such as dandruff for head lice. It’s important to know what to look for so that you can treat head lice effectively:  Use a fine-toothed comb to examine the hair and scalp for lice and nits. Live head lice are about the size of a sesame seed (between 2-3mm long). Nits, or lice eggs, are usually yellowish white and stick onto hairs near the scalp. They are slightly smaller than adult lice.  Look for nits that are stuck to t