Modify Search Incident Form to search by


I am using SM 9.62 and I would like to be able to search for incidents that belong a certain service recipient which is defined in field contact.service BUT we want to conduct the search by employee id defined by field in file contacts so the returned list of incidents would be all incidents opened for this employee id.

I have added the field Emp ID on form as per the attached screenshot and I set the input field for it but it seems I need to modify the running query somewhere to reflect searching by this field which is not present in the probsummary file.

Any help where and what should I do.