Perhaps you should try some spelling variations:
_quality control » quality control, byquality control, quality controls
2c reliability » 2 reliability, 20 reliability, 24 reliability
11 reliability » 1 reliability, 3 reliability, 2 reliability
4 reliability » 3 reliability, 2 reliability
5 reliability » 3 reliability
4 safety » 5 safety
a safety » a safe

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 (((11 reliability) OR (((4 reliability) OR (5 reliability))))))%((((4 safety) OR (a safety))) OR (_ safety)) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%_quality control%((2c reliability) or (((11 reliability) or (((4 reliability) or (5 reliability))))))%((((4 safety) OR (a safety))) or (_ safety)) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %_quality control%((2c reliability) or (((11 reliability) or (((4 reliability) or (5 reliability))))))%((((4 safety) OR (a safety))) or (_ safety)) and risk%22*.