I am using GSA 7.2, In GSA Search Report It have two Report types

* Searches that returned results
* Searches that did not return results

what is difference between this types?

I tried Last week Search Report with both types, I am getting few same Keywords and Queries in Both Report types with different Occurrences count. Here my question is if GSA is showing result for some Keywords and Queries then It should not show in without result type, May be my Understanding is wrong, Please correct me.

Thank you for help