What is this? like a capacitors?

@hoangnhatng it is a bit hard to see. It is not a capacitor but looks more like a mercury switch or similar. Can you tell us more about where you removed it from and if there is any movement within the glass when you roll it to the side. If so it is a switch. If you can, try to post some clearer images with your question. Use this guide Adding images to an existing question for that.