Perhaps you should try some spelling variations:
_quality control » byquality control, quality controls, qouality control
29 reliability » 2 reliability, 9 reliability, 20 reliability
23 safety » 3 safety, 13 safety, 22 safety
2 safety » 4 safety, 3 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))%29 reliability%((23 safety) OR (((2 safety) OR (5 safety)))) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((_quality control) or (quality control))%29 reliability%((23 safety) or (((2 safety) OR (5 safety)))) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %((_quality control) or (quality control))%29 reliability%((23 safety) or (((2 safety) OR (5 safety)))) and risk%22*.