The original title is 鲁西西奇遇记. An animation released in 1989 in the People's Republic of China. It is based on the novel "Pipilu and Luxixi" by Yuan-jie Zheng. As of November 6, 2020, a small number of screenshots and signs were found. But, However, the original novel has been published for decades and can be found out.
There is a book drawn in a picture similar to the poster.[1] The original novel was released in the early 1980s, so it is not the original one.