Perhaps you should try some spelling variations:
22quality control » byquality control, forquality control, quality controls
_quality control » byquality control, quality controls, qouality control
29 reliability » 2 reliability, 20 reliability, 24 reliability
9 reliability » 3 reliability, 5 reliability, 2 reliability
23 safety » 3 safety, 13 safety, 22 safety
2 safety » 5 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: %((22quality control) OR (((_quality control) OR (quality control))))%((29 reliability) OR (9 reliability))%((23 safety) OR (2 safety)) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((22quality control) or (((_quality control) or (quality control))))%((29 reliability) OR (9 reliability))%((23 safety) or (2 safety)) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %((22quality control) or (((_quality control) or (quality control))))%((29 reliability) OR (9 reliability))%((23 safety) or (2 safety)) and risk%22*.