Single sentence hints that should help you in finishing each ending per chapter. Keep in mind these are just *hints* and are meant to be used along with the context of your playthrough. If you'd rather have a straightforward answer just leave a comment. 

本游戏解谜难度不高，建议实在卡关了再来看攻略。 

Guide to call the secret phone number found on the official soundtrack for the game 

Critters for Saleが日本語で遊べるようになるパッチです。攻略情報も少し。 

Подробное описание, как получить все концовки в игре и, соответственно, достижения.