How do I open this?

[NLFW]

How do I open this door? https://i.gyazo.com/1d52ec5f1281ae8fcf4640b3c072e388.png

I tied breaking rocks everywhere in the surrounding room, but couldn't find any way to get to the other side of the door or the other small room, can someone help please? I'm at endgame, I have (I think) every item and skill. Thank you in advance

[Lavesson]

Hint 1: Are you sure you have found everything you can?

Hint 2: You should have 2 out of 3 combat charms at this point

[NLFW]

Ok I did a little more exploring and I found a couple of bottles and the second combat charm, but I fail to see how it can help me open the door. Can I have another hint please? Or just spoil it to me, I'm at the Inner Sanctum boss, which I think is the final boss, and I don't want to clear the game yet. Oh another thing, is jade sword the best sword? Or does a +4 atk sword exist? thanks

[Lavesson]

Sure thing.

Door hint: Head to the door again
Door solution: Door is simply shut if you haven't collected all previous combat charms

Jade is the best sword.