Perhaps you should try some spelling variations:
_quality control » quality control, byquality control, qouality control
quality controls » quality control, qualite controle, quality concepts
5 reliability » 3 reliability
2 reliability » 3 reliability
4 safety » a safety, 5 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 controls))%((5 reliability) OR (2 reliability))%((4 safety) OR (_ safety)) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((_quality control) OR (quality controls))%((5 reliability) or (2 reliability))%((4 safety) or (_ safety)) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %((_quality control) OR (quality controls))%((5 reliability) or (2 reliability))%((4 safety) or (_ safety)) and risk%22*.