I took the time to stumble around in the dark to find precious collectibles, and thought I would take some screenshots, just in case you had some trouble finding some of them. I hope you can find what you're looking for with my help.

All cards need to be collected in a single playthrough, so collecting them here and there won't work for the achievement.

1. In the starting room against a vending machine.
2. Under a desk in the room with your bag across the hall from the starting room.
3. To the left after leaving the starting room, there is a break room. The card is on a chair toward the far left corner.
4. Under a bench as you are about to leave the nursing home.
5. Under the van just outside the nursing home.
6. Turn left after leaving the nursing home and circle around the building until you find a vending machine. The card is on top of it.
7. Near the vending machine with the card on it, there is a set of stairs. At the very top of the stairs is this card.
8. This card is on the ground along the back of the building, between the planters.
9. There are two signs for the nursing home as you are about to leave the plaza. This card is at the base of the sign to your right as you face the street.

10. After leaving the parking lot from the first building, you will see a phone booth and a set of stairs on the first building on the street. This one is at the top of the stairs.

11. Against the wall behind the first building on the street.

12. The third building down the street has a card on it's doorstep out front.
13. The last building to your left on the street before you start walking uphill will have this card tucked just behind a short wall.

14. Leaning against a brick at the start of when you begin to walk uphill.

15. Just before you start walking uphill, there's a road to the right that doesn't let you walk too far along it. This card is on the curb to the left as you look down the road.

16. When you reach the house, crouch and turn left. The card will be tucked under a short wooden roof.

17. Outside in a corner behind a bush to the left of the house's entrance.

18. On top of the big rock in the backyard near the van. The rock is the one in front of the window Souichi-san looks out from.

19. Inside the stump of a tree by the shed in the backyard.

20. The first room to your right when you walk into the house has a card poking out of a blanket in the right side of a closet.

21. In the room with the toilet.

22. Poking out of a box next to the painting and the vase.
23. Upstairs in the house in the room with a fallen clock, this card is behind a box.
24. Upstairs in the house, this card is poking out from behind a cabinet by the window.

25. Behind the door inside the shed.

26. Near you when you enter the attic.

27. Against a planter behind the desk at the lobby of the nursing home. The area will first be available after putting Souichi-san to bed.

28. Under a vending machine outside Sachie-chan's apartment.

29. If you circle around Sachie-chan's apartment to the left to a dead end, this card will be on the ground next to a planter.

30. To the right after wrecking the guy in a game of Rock-Paper-Scissors.

31. Behind a painting on Sachie-chan's apartment.

32. To the right inside the bedroom with the crowbar and bloody note.