Perhaps you should try some spelling variations:
"improving urban performance series." » "improving urban performance studies.", "improving urban performance size.", "improving bank performance series.", "improving loan performance series.", "improving human performance series."
"improving shared performance case." » "improving sharia performances case.", "improving sharing performance case.", "improving care performance case.", "improving stored performance case.", "improving sales performance case.", "improving shared performance based.", "improving shared performance chapter.", "improving shared performance 2019."

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• Performing a fuzzy search may retrieve terms with similar spellings: (("improving urban performance series.") or ("improving shared performance case."))~.
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