In this hydraulic filter symbol the flow will come from the top because there is a bypass check valve shown on the side to protect from over-pressurisation if the filter clogs.
The symbol also shows a visual clogging indicator.
This symbol shows a water cooler for a hydraulic system. The water flow paths are not shown but can be included.
This image shows four different types of accumulator.
First left is a gas pressurised accumulator with the media separated by a diaphragm.
Second left is a gas pressurised accumulator with the media separated by a bladder.
Third left is a gas pressurised accumulator with the media separated by a piston.
On the right is gas backup bottle.