Perhaps you should try some spelling variations:
optimum processing » optimum pressing (Expand search), minimum processing (Expand search), optical processing (Expand search)
decrease optimum » discrete optimum (Expand search), decrease sodium (Expand search), reverse optimum (Expand search)
decrease flow » decreases flow (Expand search), decrease low (Expand search), decrease food (Expand search)
flow decrease » flow increase (Expand search), to decrease (Expand search), or decrease (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 _ decrease optimum processing ) OR ( decrease NOT decrease flow decrease ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( decrease _ decrease optimum processing ) OR ( decrease not decrease flow decrease ))~".
• Adding a wildcard symbol may retrieve word variants: (( decrease _ decrease optimum processing ) OR ( decrease not decrease flow decrease ))*.