Perhaps you should try some spelling variations:
"international policy economic services" » "international poverty economic services", "international prices economic services", "national policy economic services", "international policy economics series", "international policy ecological services", "international policy economic studies"
"international political economic theories" » "international political economy theories", "international ecological economics theories", "international political economic theory", "international political economics series"

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