★Selected and recommended as one of the early childhood picture books by experts from Ministry of Education in 2021;
★A Growing Book written by Mei Zihan, a children’s writer and illustrated by Tian Yu, an illustrator of original picture book;
★An enjoyable and amusing book in book, allowing readers to travel through various time and space;
★Ingenious staining techniques to show the unique quality of life;
★Rich visual details, allowing readers to have new discoveries each time;
★Suitable for children and adults, allowing them to knock the door and gain new knowledge.
★ Lead children to bravely knock on the door and constantly explore the vast world!

★Awards:
“The Picture Book Award with the Most Scientific Early Education Temperament” designated by CCNG Children's Early Scientific Education Association
"The 2017 High Quality Picture Book" selected by Sina Childcare Channel
“The Excellent Book Award” selected by Young China
Listed in the top 30 of Shenzhen's "Top Ten Children's Books", the top 10 in the picture book group
2017 Laureate Children's Book Winner
Top10 of “Original Children's Books in Mom's Eyes" Jury Award of Magic Reading Organization
Top 10 Original Picture Books in 2017
The 2nd JD.com Literature Awards Annual Children's Picture Book - Original Works Award TOP5
One of the 100 publications recommended by National Press and Publication Administration in 2018

This book tells the story of a little bear's "knocking" journey. It continuously knocks on the door, and eventually more and more people join the knocking team. The little bear not only gained new friends and various surprises in its growth, but also went higher and farther, seeing a wider world…
The clever thinking and creative techniques combined with graphics and text in this book are very groundbreaking and unique, making it a book full of wit and humor.

About the Author
Mei Zihan is a romantic writer, literature professor, literature orator, children's reading lamplighter, children's literature writer, professor of Shanghai Normal University, member of Chinese Writers Association, and tutor of Central Academy of Fine Arts Picture Book Studio.
His children literature works includes “Daughter's Stories”, “A Complete Biography of Dai Xiaoqiao Series”, etc. He writes and edits multiple theoretical works, like “On the Narrative Style of Children's Novels” and so on.

About the Illustrator
Tian Yu is a famous picture book writer and painter. He graduated from the Academy of Fine Arts of Tsinghua University and later taught in the picture book creation studio of Central Academy of Fine Arts. He is deeply loved by students and is known as the "God Teacher of the Central Academy of Fine Arts"
His main works includes “I Defeated the Sleeping Monster with 32 Farts”, “THE RAT-A-TAT BEAR”, and “Lord of the Flies” and so on. He has won multiple awards, including the Second Picture Book Era Award and the 2017 Top 10 Original Picture Book Rankings. His painting style is vivid and humorous, highly creative and imaginative, close to children's aesthetics.