Each owner should be aware of “unwanted tenants” of their dog. This article is good as it shows and explain each parasites inc picture. I would advise to check inside the poo by smashing it after a worming tablet. You can use a stick or poo bag too. Very often owners don’t check and don’t know if there are any or not. However, if your dog has it needs to be repeated after 7 days again.
It is very similar treatment with humans. One dose and then second dose to kill next part.