Perhaps you should try some spelling variations:
"improving external performance metrics." » "improving emotional performance metrics.", "improving materials performance metrics.", "improving thermal performance metrics.", "improving external performance measures.", "improving maternal performance metrics.", "improving central performance metrics.", "improving federal performance metrics."
"improving rural performance targets." » "improving euract performance targets.", "improving larval performance targets.", "improving pupil 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 rural performance targets.") or ("improving external performance metrics."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("improving rural performance targets.") OR ("improving external performance metrics.")).
• Removing quotes may allow a broader search: (( improving rural performance targets. ) or ( improving external performance metrics. )).
• Adding a wildcard symbol may retrieve word variants: (("improving rural performance targets.") or ("improving external performance metrics."))*.