Multilple monitors from one laptop?

Hi,

I was wondering what I would need in order to display two seperate (extended) output from one laptop?

I have a laptop and I've been using dual monitors (24"monitor) via HDMI. I recently got a Cintiq 13HD and have tried a HDMI splitter but it only allows me to have one extended display (24" monitor) and it is duplicated onto my Cintiq.

Is there a sort of USB video adapter I could use to have two seperate extended displays somehow?

(Sorry if this seems silly, I have tried to research myself but only managed to get vague results)

It's very finicky when exiting a full screen game, but other than that this works pretty well.

I wonder if they make USB 3.1 versions yet with even more ports