How to search in a Subject Category on the Web of Science

I need to search only in journals listed in the ‘HEALTH POLICY & SERVICES’ subject category which includes 64 journals. I found a page on Web of Science Help which suggests the use of WC (e.g., WC=(HEALTH POLICY & SERVICES)) in advance search but that seems to be an old code…

To make it a bit more clear, ‘research areas’ classification doesn’t solve my problem. I know after searching for a term I can customize the search based on ‘research areas’, but those research areas are different from ‘subject categories’.

Any help is appreciated.