Perhaps you should try some spelling variations:
decrease cooperation » defense cooperation (Expand search), decrease proliferation (Expand search), decrease migration (Expand search)
cooperation effect » cooperation effects (Expand search), cooperative effect (Expand search), cooperative effects (Expand search)
decrease burden » disease burden (Expand search), decrease further (Expand search)
burden decrease » burden disease (Expand search), urea decrease (Expand search), burgers decreases (Expand search)
decrease the » decreases the (Expand search), decrease in (Expand search)
the decrease » to decrease (Expand search), and decrease (Expand search)
decrease of » decrease in (Expand search)
of decrease » or decrease (Expand search), not decrease (Expand search), to decrease (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 burden decrease the decrease ) OR ( decrease of decrease cooperation effect ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease burden decrease the decrease ) OR ( decrease of decrease cooperation effect ))*.