Perhaps you should try some spelling variations:
"world economic and financial systems." » "world economic and financial statements.", "world economic and financial sectors."
"world economic and financial sectors." » "world economic and financial sector.", "world economic and financial support.", "world economic and financial history."
"world economy and financial series." » "world economy and financial service.", "world economy and financial studies.", "world economy and financial stress."
"world economic and financial system." » "world economic and financial sector."

Try widening your search to All Fields.

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

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