Perhaps you should try some spelling variations:
decrease risk » decreased risk (Expand search), increase risk (Expand search), decrease in (Expand search)
risk decrease » risk decreases (Expand search), risk increase (Expand search), break decrease (Expand search)
decrease the » decreases the (Expand search), decrease in (Expand search), decrease of (Expand search)
the decrease » to decrease (Expand search), and decrease (Expand search)
the mastery » the master (Expand search), the mystery (Expand search), the masters (Expand search)

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decrease the decrease NOT decrease ) OR ( decrease risk decrease the mastery ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease the decrease NOT decrease ) OR ( decrease risk decrease the mastery ))*.