Perhaps you should try some spelling variations:
decrease lesions » disease lesions (Expand search), decreased response (Expand search), decrease adhesion (Expand search)
lesions decrease » response decrease (Expand search), lesions case (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 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)
decrease or » decrease of (Expand search), decrease on (Expand search), decrease pro (Expand search)
or decrease » of decrease (Expand search), not decrease (Expand search), to 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: (( decrease AND decrease OR decrease ) OR ( decrease lesions decrease covid objects ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decrease and decrease or decrease ) OR ( decrease lesions decrease covid objects ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease and decrease or decrease ) OR ( decrease lesions decrease covid objects ))*.