Perhaps you should try some spelling variations:
"improving animal performance series." » "improving animal performance studies.", "improving animal performance size.", "improving annual performance series.", "improving fiscal performance series.", "improving social performance series.", "improving initial performance series.", "improving optimal performance series.", "improving criminal performance series."
"improving thermal performance series." » "improving thermal performance studies.", "improving thermal performance size.", "improving external performance series.", "improving erm performance series.", "improving federal performance series."

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• Performing a fuzzy search may retrieve terms with similar spellings: (("improving animal performance series.") or ("improving thermal performance series."))~.
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