Perhaps you should try some spelling variations:
"international port economy series" » "international ports economy series", "international report economy series", "international airport economy series", "international port economics series", "international porn economy series", "international export economy series", "international host economy series"
"national poverty economies series" » "national poverty economic series", "national property economic series", "national diverse economies series", "national poverty economics series", "national poverty economies emdes"

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

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