how can i go b04?

[Fasic]

I stuck in b03 I cannt go b04 plz

[Wlerin]

What have you explored? Have you found the Workshop? West Area: Mine A? West Area: Mine B? I assume the answer to the third question at least is no, otherwise this thread wouldn't exist.

B03 has two things the previous floors didn't, a West Area, and ramps/stone stairs that blend in with the terrain more than ladders, but if you check your map you should be able to find your way down.

[Fasic]

holy..... thanks I missed west side. I really appreciate. have fun days

[stretch]

This wont help you for this particular issue but one trick I have figured out when lost underground is to 'track path' for an NPC from your quest log and it can help you find an elevator/lift.
I am not sure if it will take you to a lift you have not discovered and/or powered up yet but it might. I thought it did but can't be sure off the top of my head.
Might save you asking for directions next time you get stumped. Or not.
Good luck.