Delve (verb)

1. To make an investigation or research into something.
2. To explore, examine or search deeply into something.

Origin:

Delve comes from the old english word "delfan" which means "to dig" and it was adopted in english in the 14th century.

Examples:

1. He delved into the history of the city.
2. She delved into the mystery of the missing money.
3. He delved into the depths of the ocean.
4. He delved into the causes of the disease.
5. She delved into the meaning of the poem.