Perhaps you should try some spelling variations:
"international crises economic series" » "international crisis economic series", "international crimes economic series", "international cases economic series", "international crime economic series", "international prices economic series", "international crises economics series", "international crises economy series", "international crises economic theories"
"international aid economic services" » "international airshow economic services", "international airport economic services", "international aid economics series", "international aid ecological services", "international aid economic studies", "international rapid economic services", "international aids economics services", "international avoid economic services"

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

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