I don't know if I installed these correctly but I connected 1 can from the PCV valve to the intake manifold. Then, not sure about this 1, I installed the second because it seems like the same concept, from (between) just under the PCV valve to the intake chamber.
There are 2 other vacuum hoses that run to the intake chamber, not sure if anything should be done with those.
The Oil Catch Cans are 2 different basic and cheap Amazon specials.