Since we don't know exactly what it refers to, it's tough to name examples. But if it's about three things related to a true story, it could be like a movie about three siblings who overcame real - life hardships together. Or a book about three historical battles that changed the course of a region's history.
As the concept is not clearly defined, it's a bit of a challenge to give examples. However, it might be something like a play that tells the story of three individuals from different walks of life during a particular era in history, all based on real people or events. Another possibility could be a series of short stories where each story focuses on one of three related real - life events, and together they form a 'triada'.