All of this is a roundabout way of saying that "Young Hearts" is a really rare song and video, particularly for our non-Australian readers. It is by The Little Heros, a Melbourne band that formed in 1980. The group was comprised of veterans of the Melbourne pub rock scene and was led by guitarist/singer Roger Hart-Wells, along with an ever-changing lineup around him.
The band released their self-titled debut in 1981, but it was their second LP, 1982's Play By Numbers that helped them break out in their native Australia. That album featured two successful singles, "One Perfect Day" (#12) and "Young Hearts" (#42). Unfortunately, while the LP reached #37 in their home market, it did not generate any real traction in other countries.
The Little Heroes released a follow-up album in 1983 (Watch the World), which performed worse than its successor, and broke up the following year. Roger Hart-Wells would go on to become a writer and meditation coach, and most of the other members of the group likewise left the industry.