Anna has three endings - the main one (meet with Anna) is described in the walkthrough. Remaining ones are tagged in the solution with ATTENTION text. Below are more specific details about two other endings.
Ending 1 - To complete the game in this way you can NOT meet with black ghost who will show up in near main door after leave the room with a puddle (after puzzle with ritual dagger). So don't get close to the ghost but quickly move to the left side of the room and start solving puzzle with leaves and drawings. After that pass through the door with lots of eye, enkindle the lamp and move to the wall on the right side of the room. You will find a lever (picture), pull it and get out of the house through the main door.
Ending 2 - On the attic after the sequence with pouring the red symbol with blood move to the door on the right side (picture) open them with Anna's key and leave the house.