Perhaps you should try some spelling variations:
"international policy economic series" » "international poverty economic series", "international prices economic series", "national policy economic series", "international policy economic services", "international policy economic theories", "international policy economic surveys"
"international political economy survey" » "international political economic survey", "international political economic surveys", "international political economy strategy"

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

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