During his career, he primarily wrote songs for other artists, including Marta Kubišová, Helena Vondráčková, Václav Neckář, and Petra Janů.

[2] In the early days of his musical career, Petřina accompanied Marta Kubišová, Václav Neckář, and Helena Vondráčková in the Rococo Theater Orchestra, from which the group Golden Kids was formed.

In 1978, Petřina released his debut album, Super – robot, which he produced together with his friend, musician and lyricist Zdeněk Rytíř.

In the second half of the 1980s, Petřina wrote several songs for singer Eva Hurychová and returned to Václav Neckář to help him write the hard rock album Pod komandem lásky, which was released in 1988.

He also composed songs for other musicians, including Hana Zagorová, Jiří Korn, Jitka Zelenková, Petr Rezek, Michal Prokop, and Aleš Brichta.