Perhaps you should try some spelling variations:
"improving criminal performance series." » "improving critical performances series.", "improving regional performance series.", "improving animal performance series.", "improving critical performance series.", "improving civil performance series.", "improving criminal performance studies.", "improving criminal performance size."
"improving loan performance evidence." » "improving local performance evidence.", "improving land performance evidence.", "improving lead performance evidence."

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