When Hazrat Abu Zar (radhiyallahu ‘anhu) heard the report of his brother, Hazrat Unais (radhiyallahu ‘anhu), he said, “My heart is not yet fully satisfied and convinced.”

Most probably, Hazrat Abu Zar (radhiyallahu ‘anhu) wanted to hear a detailed description of Rasulullah (sallallahu ‘alaihi wasallam) and the stories regarding him. The report of his brother was too concise and was thus insufficient for him and could not satisfy him.