K8050/ connect 2 of them with one remote

Good day to all, i build a model ship 1.25 scale. And i make all lights working on board. Now i need about 28 switch numbers. Now i have one Velleman K8050(just 15 switch numbers) with a remote(works perfect). Now i reed that you can connect more K8050 with one remote. Can someone tell me what i need to make 2 K8050 with one remote. So i need the product numbers and some instruction to make it. Thanks from the Netherlands Remy