Dredge (verb)

1. To dig, scoop, or otherwise remove material from the bottom of a body of water, typically to deepen or clear a channel.
2. To search diligently or persistently for something.
3. To bring up something from memory or from a previous statement or conversation.

Origin:

From middle english dreggen, from old english dreggian, from proto-germanic *dreggōn.

Examples:

1. The river was dredged to improve navigation.
2. The lake was dredged to remove silt and improve water quality.
3. They dredged the seabed for treasure.
4. She dredged up memories of her childhood.
5. He dredged through the paperwork to find the missing documents.