This expression, which is from The Book of Songs, was originally a subtle piece of advice to King Xuan of Zhou （？-782 BC） to recruit talented recluses to work for his country. Later, it became an allegory of using criticism from others to correct one’s own mistakes, and drawing on the experiences and practices of other people or other countries to improve oneself. This phrase expresses the open-mindedness of the Chinese people and their eagerness to benefit from others’ practices.

The garden is so lovely, / Where tall sandalwood grows, / Below are short and slender mulberry trees. / There are stones on its rockeries, / Which can be used to polish jade. (The Book of Songs)