Perhaps you should try some spelling variations:
"improving building performance metrics." » "improving teaching performance metrics.", "improving building performance measures.", "improving guiding performance metrics.", "improving living performance metrics.", "improving reading performance metrics."
"improving air performance contract." » "improving air performance contracts.", "improving zur performance contract.", "improving bar performance contract.", "improving der performance contract.", "improving _ performance contract."

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