Perhaps you should try some spelling variations:
decreases sperm » decreased sperm (Expand search), decreases serum (Expand search), decreasing sperm (Expand search)
sperm decrease » term decrease (Expand search), speed decrease (Expand search), speed decreases (Expand search)
decrease covid » increase covid (Expand search), increased covid (Expand search), disease covid (Expand search)
covid objects » moving objects (Expand search), coated objects (Expand search), sound objects (Expand search)
decrease not » decrease of (Expand search), decrease akt (Expand search), decrease at (Expand search)
not decrease » to decrease (Expand search), not increase (Expand search), and decrease (Expand search)
in decrease » in decreased (Expand search), on decrease (Expand search), pain decrease (Expand search)

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (( decreases sperm decrease in decrease ) OR ( decrease NOT decrease covid objects ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decreases sperm decrease in decrease ) OR ( decrease not decrease covid objects ))~".
• Adding a wildcard symbol may retrieve word variants: (( decreases sperm decrease in decrease ) OR ( decrease not decrease covid objects ))*.