Perhaps you should try some spelling variations:
semen processing » semantic processing (Expand search), soybean processing (Expand search), grain processing (Expand search)
decreased ratio » decreased rate (Expand search), decreased native (Expand search), decreased rankl (Expand search)
ratio decrease » rate decrease (Expand search), rapid decrease (Expand search), ratio increase (Expand search)
decrease semen » decreased semen (Expand search), decrease human (Expand search), decrease need (Expand search)
decrease lipid » increases lipid (Expand search), increased lipid (Expand search)
lipid decrease » rapid decrease (Expand search), ligand decrease (Expand search), limb decrease (Expand search)
decrease and » decreases and (Expand search), decrease in (Expand search), decrease of (Expand search)
and decrease » and decreases (Expand search), and decreased (Expand search), and increase (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: (( decreased ratio decrease semen processing ) OR ( decrease AND decrease lipid decrease ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decreased ratio decrease semen processing ) OR ( decrease and decrease lipid decrease ))~".
• Adding a wildcard symbol may retrieve word variants: (( decreased ratio decrease semen processing ) OR ( decrease and decrease lipid decrease ))*.