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