Perhaps you should try some spelling variations:
"international policy economic studies" » "international poverty economic studies", "international prices economic studies", "national policy economic studies", "international policy economic status"
"international policy clinical services" » "international poverty clinical services", "international prices clinical services", "national policy clinical services", "international policy medical services", "international policy political services"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("international policy economic studies") or ("international policy clinical services"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international policy economic studies") OR ("international policy clinical services")).
• Removing quotes may allow a broader search: (( international policy economic studies ) or ( international policy clinical services )).
• Adding a wildcard symbol may retrieve word variants: (("international policy economic studies") or ("international policy clinical services"))*.