Perhaps you should try some spelling variations:
"international political economic services" » "international policy economic services", "international ecological economics services", "international political economics series", "international political ecological services", "international political economic studies"
"International political economy studies" » "International political economic studies", "International political economy series"

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