After you jump out of the window, look for a small shop with descending stairs. Enter it and notice the bookcases in it. Use the middle one to reveal the secret.
After the car tries to run over you, climb on top of it and run-jump towards the far edges of the nearby buildings. After, climb to the upper levels using the wires with the decorations. Look around to spot an alcove with a Fortune Cookie, which is the secret.
Soon after the car, is a shop to your right. Right at the entrance is a painting on the wall. Use it to make it slide and reveal the secret.
Still in the same shop as the last secret, ascend the stairs and, once at the top level, look between the doors for a crack. Blow it up for the secret.
In the same place that you get the Yellow key, the middle window near you is actually fake and can be walked through. Do so to get credited the secret.
In rooms with the register machine (which is locked by the Yellow key), use the register to make a wall to your right slide and reveal the secret.
In the other room locked by the Yellow key, notice the two phones right in front of the door. Use the left one (you should hear a gong sound to indicate it's the correct one) and a small alcove in the left wall reveals itself, which is the secret.