My dog has chronic diarrhea with yellow droplets. What tests should I ask for?

Has he had fecal testing run at a laboratory? Sometimes if the vet looks at it themselves they can miss something (human error happens). You can actually send the test in yourself to the lab and then if there are any positive results you can consult with your vet about treatment. This is the same lab they would likely use.

( https://www.idexx.com/en/veterinary/fecalchek/ )

Chronic diarrhea can be due to many different things. It may take a lot of testing to figure this out.

( https://vcahospitals.com/know-your-pet/diarrhea-in-dogs )

If it is not intestinal parasites the next most likely thing would be inflammatory bowel disease. To get a definitive diagnosis intestinal biopsies would be needed. That being said, if owners cannot afford that, often times we do a trial of medication (I use Tylosin) to treat it and see what happens.

In the meantime, I suggest you try using Fortiflora probiotic (if you have not already done so). One packet on food daily - one box will do a 30 day treatment.

( 1800petmeds.com/Purina+FortiFlora-prod10376.html )

Also, give him only his food and nothing else. The more different things you give him the more chance of diarrhea and then you won't know what is helping or not helping. Keeping things consistent makes it easier to get a diagnosis.

Hope this helps. If you have more questions you can always opt for a private consultation where we can chat back and forth. That way you can ask as many questions as you'd like. Best wishes.