Perhaps you should try some spelling variations:
"international political economic surveys" » "international policy economic surveys", "international political economy surveys", "international ecological economics surveys", "international political economic studies", "international political economic systems"
"international best ecological services" » "international best hydrological services", "international best clinical services", "international best meteorological services", "international bank ecological services", "international business ecological services", "international forest ecological services", "international term ecological services", "international key ecological services"

Try widening your search to All Fields.

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

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