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

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