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

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 economy and financial systems.") OR ("world economy and financial system."))) or ("world economic and financial series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("world economy and financial systems.") OR ("world economy and financial system."))) OR ("world economic and financial series.")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"world economy and financial systems.\") OR (\"world economy and financial system.\"))) or (\"world economic and financial series.\"))".
• Removing quotes may allow a broader search: (((( world economy and financial systems. ) OR ( world economy and financial system. ))) or ( world economic and financial series. )).
• Adding a wildcard symbol may retrieve word variants: (((("world economy and financial systems.") OR ("world economy and financial system."))) or ("world economic and financial series."))*.