Perhaps you should try some spelling variations:
22quality control » quality control, byquality control, forquality control
_quality control » quality control, byquality control, quality controls
29 reliability » 2 reliability, 9 reliability, 24 reliability
2 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))%29 reliability%2 safety AND risk%22.
• Adding a wildcard symbol may retrieve word variants: %((22quality control) or (_quality control))%29 reliability%2 safety and risk%22*.