Did you find the "little egg" in the promotional film "Everything has Poetry" of UnionPay poetry POS machine?

Regarding the promotional film "Everything has Poetry" of UnionPay poetry POS machine, I wonder if you have noticed that at the end of the short film, after the little boy found his poem, a train passed by in the distant mountains in the picture, which was the highlight of the whole night, echoing the full moon in the sky. This may be the train that the little boy wants to find his mother, which makes us suddenly feel the loneliness of the little boy and the yearning for his mother. In fact, in the offline activities of the UnionPay poetry POS machine, China UnionPay also put the children's poems on the "Fuxing". By reciting their own poems, children also let more people feel their talents and participate in this activity.