Perhaps you should try some spelling variations:
"improving urban performance reviews." » "improving urban performance review.", "improving urban performance reports.", "improving urban performance risks.", "improving bank performance reviews.", "improving loan performance reviews.", "improving human performance reviews."
"improving co performance series." » "improving co performance studies.", "improving co performance size.", "improving ceo performance series.", "improving do performance series.", "improving core performance series.", "improving eco performance series.", "improving crop performance series.", "improving ict performance series."

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 reviews.") OR ("improving co performance series."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"improving urban performance reviews.\") OR (\"improving co performance series.\"))".
• Removing quotes may allow a broader search: (( improving urban performance reviews. ) OR ( improving co performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving urban performance reviews.") OR ("improving co performance series."))*.