Well, as others have already noted, your character can't use charisma to find secret doors, absent very specific circumstances (such as finding an NPC that knows where they are and persuading them to tell you).
On the other hand, you, the player, can!
You can intimidate the DM. Nice game you got here. Shame if anything happened to it. Say, are there any secret rooms in here?
You can persuade the DM. I hear your partner needs a new coat. What's that $100 bill doing by the DM screen? Anyway, any secret doors in here?
You can deceive the DM. I heard some weird noises coming from the kitchen- you should check it out. I'll make sure no one looks at the map while you're gone.