Perhaps you should try some spelling variations:
"improving social performance metrics." » "improving social performance measures.", "improving school performance metrics.", "improving fiscal performance metrics.", "improving financial performance metrics."
"improving und performance series." » "improving und performance studies.", "improving und performance size.", "improving fund performance series.", "improving funds performance series.", "improving good performance series.", "improving food performance series.", "improving burn performance series.", "improving feed performance series."

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 und performance series.") OR ("improving social performance metrics."))~.
• Removing quotes may allow a broader search: (( improving und performance series. ) or ( improving social performance metrics. ))~.
• Adding a wildcard symbol may retrieve word variants: (("improving und performance series.") or ("improving social performance metrics."))*.