Perhaps you should try some spelling variations:
"improving urban performance series." » "improving urban performance metrics.", "improving urban performance reviews.", "improving urban performance review.", "improving bank performance series.", "improving loan performance series.", "improving can performance series."
"improving co performance series." » "improving co performance metrics.", "improving co performance reviews.", "improving co performance review.", "improving do performance series.", "improving crop performance series.", "improving job performance series.", "improving _ performance series.", "improving macro performance series.", "improving food performance series."

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: (("improving urban performance series.") or ("improving co performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving urban performance series.") OR ("improving co performance series.")).
• Removing quotes may allow a broader search: (( improving urban performance series. ) or ( improving co performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving urban performance series.") or ("improving co performance series."))*.