Perhaps you should try some spelling variations:
decrease during » increase during (Expand search), increases during (Expand search), increased during (Expand search)
during objects » using objects (Expand search), cutting objects (Expand search), warping objects (Expand search)
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 hiv » decrease in (Expand search), decrease their (Expand search), decreased high (Expand search)
hiv increase » diet increase (Expand search), acid increase (Expand search), and increase (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 hiv increase NOT decrease ) OR ( decrease risk decrease during objects ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease hiv increase NOT decrease ) OR ( decrease risk decrease during objects ))*.