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

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