Perhaps you should try some spelling variations:
_quality control » quality control, byquality control, quality controls
2c reliability » 20 reliability, 24 reliability, 29 reliability
9 reliability » 4 reliability
23 safety » 3 safety, 13 safety, 4 safety
22 safety » 12 safety, 4 safety, 3 safety
a safety » a safe
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%((2c reliability) OR (((((9 reliability) OR (3 reliability))) OR (((5 reliability) OR (2 reliability))))))%((((23 safety) OR (((((22 safety) OR (5 safety))) OR (a safety))))) OR (2 safety)) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%_quality control%((2c reliability) or (((((9 reliability) or (3 reliability))) or (((5 reliability) or (2 reliability))))))%((((23 safety) or (((((22 safety) OR (5 safety))) or (a safety))))) or (2 safety)) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %_quality control%((2c reliability) or (((((9 reliability) or (3 reliability))) or (((5 reliability) or (2 reliability))))))%((((23 safety) or (((((22 safety) OR (5 safety))) or (a safety))))) or (2 safety)) and risk%22*.