My 5month old puppy has been sick for 4 days. Not eating by himself,we feed him,but he drinks water by himself. Took him to the vet 2 times.. he doesn't do a lot, and doesn't poop. Is his illness serious or will he recover?

You want to get a different vets opinion

Indeed, a young puppy not eating is very serious. And even more worrying is the fact that he hasn't pooped.
He could have anything from parvo to a bowel obstruction.

Please take him to another vet

Take him to a different vet or your not going to have a dog for very long. :S

You state you feed him. Are you trying to force food on him because you should not do that.

If he wants to eat on his own,fine. Dogs pretty much know what do do to feel better.

Maybe his food is bad.Maybe it got moldy.Don't force him to eat.Dry dog food in the big bags gets left in a moist place and it can get moldy.

You need to be concerned that he is hydrated,give him access to cool water,Throw a bunch of ice in his bowl,dogs love that.

Stop force feeding him,if in fact that is what you are doing.Not sure about that.

Keep him cool.Do not put a blanket on him and leave him be until you can get him to the vet tomorrow.

I wish you both the best.If you are so inclined an update would be fantastic!

Had to spread the rep but very good answer artlady.
Make him as comfortable as possible until you can get him to a vet.

I think with the feeding they mean hand-feeding... like having to hold the food for the puppy to eat it?

Update would be great :)

my 5month old puppy has been sick for 4 days. not eating by himself,we feed him,but he drinks water by himself. took him to the vet 2 times..he doesnt do a lot, and doesnt poop. is his illness serious or will he recover?

Did he get into something, eat a raw hide bone, what do you mean your vet isn't saying anything, what did he eat, have you wormed him? Sounds like he ate something, if he isn't pooping, it may be lodged in his stomach lining or intestines, you need to get answers from a vet, you can try just feeding him cooked white rice, with a little chicken broth, do a 1/2 cup at first, see what happens