Perhaps you should try some spelling variations:
"international union economic series" » "international action economic series", "international joint economic series", "international education economic series", "international union economics series", "international union economic services", "international union economic theories", "international indian economic series", "international asian economic series", "international russian economic series"
"international business economy series" » "international business entry series", "international business economics series"

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

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