Perhaps you should try some spelling variations:
"international policy economic surveys" » "international poverty economic surveys", "international prices economic surveys", "national policy economic surveys", "international policy economic systems"
"international crisis economic studies" » "international credit economic studies", "international civil economic studies", "international cases economic studies", "international crisis economic status", "international crises econometric studies", "international china's economic studies"

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