Minecraft stuff kept in different worlds (Multiverse Core)?

I have a small problem.

I've created a farm, construction and spawn world with Multiverse Core.

But when I leave the farm world and go to spawn for example, all items are gone!

how can you fix that?

You have to Configure, not fixxen.

To say even better you have to set with a plugin that you have an inventory for all worlds

I think it even goes directly with multiverse core just look at the configs and the commands

Okay, thank you very much