72 hours transit visa

Hi!

We are traveling from Stockholm, Sweden to Beijing. We're having a hard time finding information if its okey to have a stopover flight to another country, stay there for an hour or two before getting on your connecting flight to Beijing and stay there for 72 hours visa-free?

So for example is it okey to fly from Stockholm, stay in Warszawa for 2 hours to take your connecting flight to Beijing? And of course having a ticket to another country from Beijing within the 72 hours.

Thanks for you help

Best Regards, Hugo and Julia