Perhaps you should try some spelling variations:
"international policy economy series" » "international poverty economy series", "international prices economy series", "national policy economy series", "international policy economic series", "international polish economy series", "international politics economy series", "international policy economics series"
"international energy economic theories" » "international energy economic theory", "international energy economics series", "international energy economics theories", "international energy economy theories", "international ecology economic theories"

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