Dragon Ball Z: Namek Saga by Akira Toriyama

This review covers chapters 48-77 (Volumes 5 and 6) of the Dragon Ball Z manga; alternatively it covers volumes 21 and 22 of the Dragon Ball manga.

Goodreads Synopsis
Its name is derived from the story arc revolving around the homeworld of the creatures on Earth believed to be demons, such as Kami and King Piccolo. It covers the trip and arrival to planet Namek, a fictional planet from the series, of Bulma, Krillin, and Gohan. The saga also covers the battles the Earth warriors and Vegeta face against Zarbon and Dodoria, Frieza's top two henchmen. Nearing the end of the chapter, it covers the arrival of Goku on Namek to aid his allies and the beginning of the fight against the Ginyu Force.