Perhaps you should try some spelling variations:
22quality control » quality control, _quality control, byquality control
qouality control » quality control, quality controls, _quality control
5 reliability » 3 reliability
2 safety » 5 safety, 4 safety, 3 safety
a safety » a safe

Try widening your search to All Fields.

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) OR (qouality control))%5 reliability%((2 safety) OR (a safety)) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((22quality control) or (qouality control))%5 reliability%((2 safety) OR (a safety)) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %((22quality control) or (qouality control))%5 reliability%((2 safety) OR (a safety)) and risk%22*.