Perhaps you should try some spelling variations:
"international project economic theories" » "international prices economic theories", "international poverty economic theories", "international policy economic theories", "international project economic theory", "international project economics series", "international projects economic theories", "international property economic theories", "international products economic theories"
"international rican economy series" » "international african economy series", "international rice economy series", "international american economy series", "international rican economics series", "international roman economy series", "international rich economy 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 project economic theories") or ("international rican economy series"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international project economic theories") OR ("international rican economy series")).
• Removing quotes may allow a broader search: (( international project economic theories ) or ( international rican economy series )).
• Adding a wildcard symbol may retrieve word variants: (("international project economic theories") or ("international rican economy series"))*.