Perhaps you should try some spelling variations:
"improving animal performance evidence." » "improving annual performance evidence.", "improving fiscal performance evidence.", "improving social performance evidence.", "improving initial performance evidence.", "improving optimal performance evidence.", "improving criminal performance evidence."
"improving thermal performance series." » "improving thermal performance studies.", "improving thermal performance size.", "improving external performance series.", "improving erm performance series.", "improving federal 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 animal performance evidence.") or ("improving thermal performance series."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving animal performance evidence.") OR ("improving thermal performance series.")).
• Removing quotes may allow a broader search: (( improving animal performance evidence. ) or ( improving thermal performance series. )).
• Adding a wildcard symbol may retrieve word variants: (("improving animal performance evidence.") or ("improving thermal performance series."))*.