How to filter SRs using Affected Party

Summary:

My client is exposing the Affected Party field on the Employee and Agent HR Help Desk Request layouts, and the agents should be able to filter and search for SRs by Affected Person. I cannot see this option in the Configure Adaptive Search under the HR Help Desk Request object or the Help Desk Contact object I can see other standard fields and I can see my custom fields but not the Affected Person, this is a must have requirement so any advise on how to achieve this would be great?

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