It is probably best that you replace the keyboard. You can cause more trouble than what's it worth trying to clean them. I don't know where you are but they cost about $50AUD in Australia
You might get some clues on how to replace the keyboard from this link. They don't state what Asus model it is but it looks similar.
If you do try to replace it yourself, just take your time and be patient. You'll see in the video that not much force is needed. I find that an old credit card (use the corner) works better than a metal screwdriver when trying to free plastic catches. It also reduces the chances of scratches and worse damage if you slip.
Maybe you should also look up and see how to replace the motherboard just so that you can check further into the laptop itself and see if the liquid got in anywhere else.