Need Explanation Categories & Parent Categories.

Hi Team,

I might be asking for a very silly question but very curious to know that, I am new to GeoDirectory.
I made multiple categories and few categories have Parent Categories in my CPT, Now my understanding is that each category will have a separate URL and that is what i got. Example Below.

https://example.com/business/category/advocates-lawyers/
https://example.com/business/category/civil-lawyers/

Now the first is the url for category Advocates & Lawyers which does not have any parent category.
2nd url belongs to a category where Advocates & Lawyers is parent category.

What i wanted to create is that if in case category does not have listings then search result should not go blank, it should be related with parent category or other category related to parent category.

Priority given in search
Main category which is being search> parent category which is associated with main category> other category which are also related to parent category.

Please give me suggestion how can we achieve that. I tried to search but did not get anything related to this topic.