Q: What are the guidelines in using the sub-problem of the study?

1 Answer to this question
Answer:

Your question isn’t entirely clear.

In case you are referring to the problem statement, you may refer to this article: The basics of writing a statement of the problem for your research proposal

In case you are referring to sub-objectives, you may refer to this query by another researcher/academic: How do I write research sub-objectives?

Hope that helps.