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

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 services") or ("international energy economics services"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international political economic services") OR ("international energy economics services"))*.
• Removing quotes may allow a broader search: (( international political economic services ) or ( international energy economics services ))*.