Here are another set of ko-so-a-do words. Like これ, それ, あれ, and どれ, which corresponds to objects of relative distances, these words correspond to relative locations.
ここ (koko) = here (near me, the speaker)
そこ (soko) = there (near you, the person being spoken to)
あそこ (asoko) = over there (far from both the speaker and listener)
どこ (doko) = where (question word)
As you can see, these words are very similar to the other ones because of ko-so-a-do. The good thing though is that the overall meaning hasn't really changed, and you probably noticed that.
こ: close to you
そ: close to listener
あ: far from both speaker and listener
ど: question word
I hope things are beginning to make sense with ko-so-a-do. It's very simple once it's understood.