Perhaps you should try some spelling variations:
2c reliability » 2 reliability, 24 reliability, 20 reliability
ic reliability » 2 reliability, 5 reliability, 9 reliability
22 safety » 2 safety, a safety, 5 safety
12 safety » 2 safety, 10 safety, 11 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 (ic reliability))%((((22 safety) OR (_ safety))) OR (12 safety)) AND risk%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%quality control%((2c reliability) or (ic reliability))%((((22 safety) OR (_ safety))) or (12 safety)) and risk%22".
• Adding a wildcard symbol may retrieve word variants: %quality control%((2c reliability) or (ic reliability))%((((22 safety) OR (_ safety))) or (12 safety)) and risk%22*.