Perhaps you should try some spelling variations:
"improving seismic performance series." » "improving economic performance series.", "improving academic performance series.", "improving seismic performance studies.", "improving seismic performance size.", "improving semantic performance series.", "improving service performance series.", "improving basic performance series."
"improving care performance risk." » "improving trade performance risk.", "improving drive performance risk.", "improving 2 performance risk.", "improving care performance 2019.", "improving early performance risk.", "improving air performance risk.", "improving data performance risk."

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

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