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