Perhaps you should try some spelling variations:
_quality control » byquality control, quality controls, qouality control
5 reliability » 3 reliability
2 reliability » 3 reliability
12 safety » 2 safety, 10 safety, 11 safety

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: %((_quality control) OR (quality control))%((5 reliability) OR (2 reliability))%((12 safety) OR (5 safety)) AND risk%22.
• Adding a wildcard symbol may retrieve word variants: %((_quality control) or (quality control))%((5 reliability) or (2 reliability))%((12 safety) or (5 safety)) and risk%22*.