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 economic surveys"
"international brief economic services" » "international relief economic services", "international border economic services", "international bridge economic services", "international brief ecological services", "international brief economic surveys", "international brief economic survey", "international tariff economic services", "international area economic services", "international drive economic 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 brief economic services"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international policy economic studies") OR ("international brief economic services"))*.
• Removing quotes may allow a broader search: (( international policy economic studies ) or ( international brief economic services ))*.