Is this grammar correct...while doing your research you found one good cases about?

No, the grammar is not quite correct. Here's why and how to fix it:

* "Cases" is plural: It should be "case" since you're likely referring to a single example.

* "About" is unnecessary: The sentence is better without it.

Here's how you can rewrite the sentence:

* "While doing your research, you found one good case."

You could also add more context, for example:

* "While doing your research, you found one good case about the effectiveness of this treatment."