It's interesting to completely open a keyboard and look how it works inside. There a many plastic sheet with conductive lines called traces. Looks like a diagram and each key has a specific trace. When you push on a keyboard key the action is transfered to a small rubber button under the key that initiate an electrical contact on the sheet traces and the chosen character is recorded by the processor and transfered to the screen so you can see it. When liquid is dropped on the keyboard it may reach the internal sheets and dissolve part of the electrical traces causing a key malfunction, the electrical current flow being interrupted. Wine can easily dissolve the traces and that can't be repaired. You have to replace the keyboard.