air flows out of the valve cover to the intakes to be sucked back into the engine

Flow direction is from pcv to upper intake plenum; check valves in these hoses prevent boosting crankcase,,,if catch cans are used-pcv to catch can inlet,catch can outlet to check valve,check valves to upper plenum (arrow to upper plenum)
Other valve cover vent pipe (near throttle bodies) vent to atmosphere w/small breather filters.