Perhaps you should try some spelling variations:
decrease during » increase during (Expand search), increases during (Expand search), increased during (Expand search)
during decrease » during increased (Expand search), during depressed (Expand search), during disease (Expand search)
decrease cells » decrease cell (Expand search), decreases cell (Expand search), decrease costs (Expand search)
cells decrease » cells decreases (Expand search), cells increase (Expand search), cells increases (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)

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 cells decrease NOT decrease ) OR ( decrease during decrease covid objects ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decrease cells decrease not decrease ) OR ( decrease during decrease covid objects ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease cells decrease not decrease ) OR ( decrease during decrease covid objects ))*.