Well, 'sh short story' is quite ambiguous. It could potentially be a short story set in a specific location, say a small town (starting with 'sh' like Shelbyville) and it could revolve around the daily lives of the people there. Maybe it's about their hopes, dreams, and the challenges they face. It could also be a historical short story, perhaps set during a significant event in a place whose name starts with 'sh'.
The 'Durarara!!' light novels are mainly about the complex and intertwined lives of various characters in Ikebukuro. It features a unique cast including Mikado Ryuugamine, a boy who moves to Ikebukuro for a new start, and characters like Celty, a Dullahan without her head. There are also elements of the supernatural, gang activities, and the exploration of human relationships in a busy urban setting.
I'm not sure specifically what 'sh secret story' is. It could be a very personal or local story. Maybe 'sh' is an abbreviation for a place, a person's name or something else. Without more context, it's hard to say more.
It depends on your preferences. Some people think it's great for its intense storylines and well-developed characters. Others might not be as impressed.