Hmm it seems the search option is out of order....
In that case, the Hag is invisible. If you are facing Mayrina, there is a beam-bridge behind her. Hit the bridge with some AoE's"area of effects" till the Hag pops out.
He is not talking about the in game search options. He is saying you need to use the search options in the forums here to find the right thread with the answer. I don't have the answer myself as i had the same problem. I am yet to seach the forums either.