Perhaps you should try some spelling variations:
"improving central performance evidence." » "improving contract performance evidence.", "improving sectoral performance evidence.", "improving entry performance evidence.", "improving mental performance evidence.", "improving critical performance evidence.", "improving energy performance evidence."
"improving loan performance series." » "improving loan performance metrics.", "improving loan performance reviews.", "improving loan performance review.", "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 central performance evidence.") or ("improving loan performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving central performance evidence.") OR ("improving loan performance series.")).
• Removing quotes may allow a broader search: (( improving central performance evidence. ) or ( improving loan performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving central performance evidence.") or ("improving loan performance series."))*.