Perhaps you should try some spelling variations:
"international ecological economic surveys" » "international technological economic surveys", "international psychological economic surveys", "international economics economic surveys", "international ecological economics surveys", "international political economic surveys", "international ecological economic studies", "international ecological economic systems"
"international wages economic theories" » "international pages economic theories", "international waters economic theories", "international water economic theories", "international wages economic theory", "international wages economics series", "international changes economic theories", "international states economic theories"

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

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