To investigate or research deeply into a subject or issue. She decided to delve into the history of her family to learn more about her ancestors.
To dig or excavate, often used in the context of digging into the ground or a surface. The archaeologists began to delve into the ancient ruins to uncover hidden artifacts.
To reach into something and search, usually with one’s hands; to rummage. He delved into his pocket and pulled out a crumpled note.