Install httpfox extension for firefox.
open httpfox, start video, find url, looking like this:
https://stream1.hocmai.vn:1940/previ...do-ngoc-ha.mp4
download wirth vlc.
Or click on this link ( open new tab, paste the link) video will play.
Right click on video, save as...
You must be quick here, error: 404 comes quick.
https://stream1.hocmai.vn:1940/previ...ran-phuong.mp4
works if you are quick. It must be some sort of ID here that gives you as long time as video runs.