As the title is quite old. Only online streaming sites are available. They are all in Korean with Chinese subtitle.

[Korea]2016 Tunnel 遂道 터널

https://gimy.ai/vod/159271.html
https://momovod.app/vod/78179.html
https://pttplay.cc/vod/190941.html
https://www.kktvn.com/detail/733.html