Perhaps you should try some spelling variations:
_quality control » byquality control, quality controls, qouality control
2 reliability » 3 reliability, 5 reliability
9 reliability » 3 reliability, 5 reliability, 4 reliability
2c safety » 2 safety, 22 safety, 23 safety
5 safety » a 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))%((2 reliability) OR (9 reliability))%((2c safety) OR (((5 safety) OR (_ safety)))) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((_quality control) or (quality control))%((2 reliability) or (9 reliability))%((2c safety) or (((5 safety) OR (_ safety)))) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %((_quality control) or (quality control))%((2 reliability) or (9 reliability))%((2c safety) or (((5 safety) OR (_ safety)))) and risk%22*.