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