Perhaps you should try some spelling variations:
decreased sperm » decreased sleep (Expand search)
lipid decreased » rapid decrease (Expand search), life decreased (Expand search)
decrease lipid » increases lipid (Expand search), increased lipid (Expand search)
decrease rate » decreased rate (Expand search), decreases rate (Expand search), decrease at (Expand search)
rate decrease » rats decreases (Expand search), rate increase (Expand search), to decrease (Expand search)
sperm skaters » speed skaters (Expand search), sea skaters (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 OR decrease rate decrease ) OR ( decrease lipid decreased sperm skaters ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease OR decrease rate decrease ) OR ( decrease lipid decreased sperm skaters ))*.