Perhaps you should try some spelling variations:
defense learning » defense planning (Expand search), deleuze learning (Expand search), defense training (Expand search)
decrease during » increase during (Expand search), increases during (Expand search), increased during (Expand search)
during decrease » during increased (Expand search), during depressed (Expand search), during disease (Expand search)
learning object » learning 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 can » decrease in (Expand search), decrease and (Expand search), decrease at (Expand search)
can defense » can defenses (Expand search), main defense (Expand search), in defense (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 during decrease risk decrease ) OR ( decrease can defense learning object ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease during decrease risk decrease ) OR ( decrease can defense learning object ))*.