Perhaps you should try some spelling variations:
"improving human performance review." » "improving human performance risk.", "improving human performance evidence.", "improving thermal performance review.", "improving company performance review.", "improving animal performance review.", "improving urban performance review.", "improving rural performance review."
"improving loan performance series." » "improving loan performance metrics.", "improving loan performance reviews.", "improving loan performance targets.", "improving poor performance series.", "improving bank performance series.", "improving _ performance series.", "improving local performance series.", "improving land performance series.", "improving road 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 human performance review.") or ("improving loan performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving human performance review.") OR ("improving loan performance series.")).
• Removing quotes may allow a broader search: (( improving human performance review. ) or ( improving loan performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving human performance review.") or ("improving loan performance series."))*.