Perhaps you should try some spelling variations:
"improving pupil performance series." » "improving pupil performance studies.", "improving pupil performance size.", "improving social performance series.", "improving model performance series.", "improving judicial performance series.", "improving public performance series.", "improving civil performance series.", "improving audit performance series."
"improving export performance review." » "improving export performance risk.", "improving export performance evidence.", "improving exposure performance review.", "improving eap performance review.", "improving eco performance review."

You may be able to get more results by adjusting your search query.

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