Perhaps you should try some spelling variations:
"improving coverage performance metrics." » "improving average performance metrics.", "improving overall performance metrics.", "improving governance performance metrics.", "improving coverage performance measures.", "improved coverage performance metrics.", "improves coverage performance metrics."
"improving firm performance series." » "improving firm performance studies.", "improving firm performance size.", "improving firms performance series.", "improving air performance series.", "improving erm performance series."

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