In the book Thief what does Lydia like to do?

You're likely referring to the novel "Thief" by Megan Whalen Turner. While the character Lydia isn't explicitly stated to have a specific hobby, she does have a few clear traits that suggest her interests:

* She loves books: Lydia is a skilled reader and is fascinated by stories. She spends a lot of time in the library, reading and learning about different cultures and histories. This suggests a love of knowledge and storytelling.

* She's observant and curious: Lydia notices details others miss and is intrigued by the world around her. She enjoys learning about people and their lives, which suggests an inquisitive nature.

* She's dedicated to her craft: As a thief, Lydia is skilled and dedicated to her work. This suggests a passion for what she does, even if it's an unconventional path.

While the book doesn't explicitly state what Lydia enjoys doing in her free time, her love of learning, her observant nature, and her dedication to her work provide insight into her interests.