How much cloaking do i need to be able to hack somebody? because i bought 2 cloak scanner things and it still said my cloaking wasnt high enough.

You have to have more cloaking than they have scanning.

Don't forget that it isn't just about how many modules you have, but how good they are; the better the tech you have is, the more cloaking you get per module deckspace requirement. (Better deckspace to bonus ratio) Concentrate on researching cloaks if you want to hack successfully.

If your ship is too small to equip more than the two modules you mentioned above, remember to unequip modules that aren't needed for hacking - weapons, shields, energy, hull. (Remember to requip them afterwards!) This will give you more space to equip more or better cloaking modules.

The lower the level of the enemy, the more likely your hack will succeed (Less player experience, less research, fewer modules) This isn't however definite. Hacking only ever has a maximum of 99% chance of succeeding.