Hi! At the moment you can't get all the scenes in one playthrough, as there are mutually exclusive points.
#20 Apology - When Anna chases the elf away and tells that she found the treasure map from her, choose an option for relationship points.
#28 Sunset Charm - On the evening of your first day on the island, stop by the distant beach and watch the girl.
Yes, the walkthrough is on patreon (it's open and free to everyone).