Where is quest to enter Dragon Cave

If that's the Nordic quest in Carmi or somewhere in Soft Bog then that will be the Mystery cave, just use this map as reference:

http://eowiki.online-ga.me/NordicMap_v1_0.jpg

This is the problem when the game is just translated from an Asian language: the translations are somewhat varying.

I know where dragon cave is.

To enter dragon cave you have to a secret quest in bosnia. I have a tele inside but I want to do the secret quest

Oh so its a different dungeon then, lemme try that one out (unless its a high level quest).. ^_^