Filter Sharepoint 2013 Search user from results

I have a farm with a two way trust with between DomainA and DomainB. I have Search service and User profile configured.

In the people search results I have users from both the domains i.e. domainA\user1 DomainB\user1

How do I filter the results.

I checked result sources but did not find a way to filter the first domain.

Is there any way to filter the DomainA\user1 from the results