Business Partner Search issue based on Roles

Hi Experts,

I am new to Web UI and I am facing a issue when using the BP search component.

The filtering has a issue when using three BP roles at a time.

Could you help me locate where could I find the logic for the filtering?

Is the below behaviour how usually standard works?

Case 1: All three BP types

Case 2: Only one BP type - here I get much more results.

Thank you.

Best regards,

Elena