Perhaps you should try some spelling variations:
22quality control » quality control, _quality control, byquality control
2 reliability » 3 reliability
5 reliability » 3 reliability
2c safety » 23 safety, 25 safety, 21 safety
22 safety » 12 safety, _ safety, a safety
2 safety » _ safety, a safety, 5 safety

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: %22quality control%((2 reliability) OR (5 reliability))%((2c safety) OR (((22 safety) OR (2 safety)))) AND risk%22.
• Adding a wildcard symbol may retrieve word variants: %22quality control%((2 reliability) or (5 reliability))%((2c safety) or (((22 safety) or (2 safety)))) and risk%22*.