Perhaps you should try some spelling variations:
"improving urban performance series." » "improving urban performance studies.", "improving urban performance size.", "improving bank performance series.", "improving loan performance series.", "improving human performance series."
"improving do performance risk." » "improving do performance 2019.", "improving di performance risk.", "improving 2 performance risk.", "improving 3 performance risk.", "improving co performance risk.", "improving eco performance risk.", "improving pro performance risk."

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