Perhaps you should try some spelling variations:
"international political economic series" » "international politics economic series", "international political economics series", "international political economies series", "international political economic studies"
"international political economic theories" » "international politics economic theories", "international political economic theory", "international political economics series", "international political economics theory"
"international political economy series" » "international politics economy series"

You may be able to get more results by adjusting your search query.

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