Besaid

Do not read unless you have played through Besaid in chapter 1

(SPOILER) Im in chapter 5 , and all i need to know is this :
Where/How do i find the SECOND set of Ciphers for the inside of the cave?

You need the search sphere. Have you rescued the tourists in the Calm Lands at Yojimbo's Fayth Cave? If you have, one of the tourists gives you the Besaid Key, which opens the locked chest in the temple. There is a search sphere inside the chest. Use the search Sphere to find the 4 numbers and you're set! The Besaid Key was 900,000 Gil in Chapter 1 but she sold it to a tourist, the tourist gives it to you free of charge when you save him in the cave. :D

Do I have to be in a certain chapter to save the tourist?

It starts in Chapter three but I think you can go in Chapter 5. Go check it out. Go see the Item Lady in Besaid and if she says that she sold the key to a tourist who went to a cave up north, that's the calm lands, go to the cave under the bridge *Yojimbos cave* and if there are people laying around and freaking out, you can still do the cave. otherwise you're SOL. If you can't get it, I have the numbers for it.

EDIT: Actually, if you talk to her she might have it again. and she'll be trying to sell it off at a super cheap price! I just remembered. But if you fight Yojimbo, it's an entry point for the farplanes and if you get all 5 entry points, you get an AWESOME grid that allows you to cast ULTIMA so it's worth it in the end.