Perhaps you should try some spelling variations:
"improving coverage performance measures." » "improving average performance measures.", "improving overall performance measures.", "improving governance performance measures.", "improved coverage performance measures.", "improves coverage performance measures."
"improving pupil performance targets." » "improving social performance targets.", "improving model performance targets.", "improving judicial performance targets.", "improving public performance targets.", "improving civil performance targets.", "improving audit performance targets."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("improving pupil performance targets.") or ("improving coverage performance measures."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving pupil performance targets.") OR ("improving coverage performance measures.")).
• Removing quotes may allow a broader search: (( improving pupil performance targets. ) or ( improving coverage performance measures. )).
• Adding a wildcard symbol may retrieve word variants: (("improving pupil performance targets.") or ("improving coverage performance measures."))*.