Best answer by chillphone
I don't have the p20 but I would recommend aiming the camera at a spot the travelling object would pass thru and hold down the shutter to take multiple shots so you will hopefully capture before and after it passed your focal point. Another traditional way is to pan with the moving object and take multiple shots. Try and ensure you have good lighting as well so you can focus quickly on the object.
If it's night possible test with the light trails setting although for this it might work best with a tripod or static support for your device.