Why are there no poems about missing parents in Han Dynasty poetry?

Han Dynasty poetry includes works that express longing for parents.

1. Confucianism in the Han Dynasty attaches great importance to filial piety, and the memory of parents is prevalent in the culture of the Han Dynasty. In "The Book of Songs·Beifeng·Kai Feng", "The Kaifeng comes from the south, blowing the thorny heart. The thorny heart is young, and the mother's family is tired." and "Drinking Horses in the Great Wall Grottoes" "Green grass by the river, lingering thoughts The long journey is unimaginable. I dreamed of it long ago. I dreamed of it being beside me, and suddenly I felt that I was somewhere else." Works such as this express my longing for and admiration for my parents.

2. There are also some mourning poems in the Han Dynasty, such as "Kingfisher" and "Dan Ge Xing" by Cai Yong, which express the nostalgia and remembrance of deceased parents.