What did Zhang Wang say about pulling carts?

You should be talking about the story of King Wen pulling a rickshaw. This story mainly tells the story of Corporal Li Xian's thirst for talents.

This allusion is about Zhou Wenwang's thirst for knowledge. When he learned that Jiang Ziya was in Weishui, he went to ask Ziya to come out of the mountain. Ziya asked King Wen to pull a rickshaw, which actually tested the fate of the Zhou Dynasty.