Perhaps you should try some spelling variations:
decreases sperm » decreased sperm (Expand search), decreases serum (Expand search), decreasing sperm (Expand search)
decrease doping » decrease during (Expand search), decrease owing (Expand search), decrease lodging (Expand search)
sperm decrease » term decrease (Expand search), speed decrease (Expand search), speed decreases (Expand search)
doping process » drying process (Expand search), dying process (Expand search), pulping process (Expand search)
decrease with » decreases with (Expand search), increase with (Expand search), decrease in (Expand search)
with decrease » with decreased (Expand search), with deceased (Expand search), with increase (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: "(( decreases sperm decrease doping process ) OR ( decrease with decrease of decrease ))~".
• Adding a wildcard symbol may retrieve word variants: (( decreases sperm decrease doping process ) OR ( decrease with decrease of decrease ))*.