In my car, there is a thermo valve with 2 vacuum hoses connected to it coming from the carburetor. My question is, how does the two vacuum functions with the thermo valve. I have noticed that when the engine is idling, only one of the hoses has vacuum, the other one does not have. Warm or cold engine, still only one hose has a vacuum. How do I diagnose this or is this normal?

Thanks in Advance.