Flight from siem reap to Guangzhou via Beijing to Amsterdam

Hello, I fly from siem reap Cambodia to Guangzhou and from there to Beijing to catch my flight to Amsterdam. I only have two hours lay overs and don't intend to visit any cities, I just want to go to Amsterdam. At the AirPort they said I need a visa but I won't leave the airports, just transit. They gave me a doen: application for stay permit. Is that enough or will I get problems? This is urgent since I fly today . Thank uou