Perhaps you should try some spelling variations:
"international political economic studies" » "international policy economic studies", "international political economy studies", "international ecological economics studies", "international political economic status"
"international social ecological services" » "international society ecological services", "international sourcing ecological services", "international seminar ecological services", "international social hydrological services", "international social clinical services", "international social meteorological 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 studies") or ("international social ecological services"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international political economic studies") OR ("international social ecological services")).
• Removing quotes may allow a broader search: (( international political economic studies ) or ( international social ecological services )).
• Adding a wildcard symbol may retrieve word variants: (("international political economic studies") or ("international social ecological services"))*.