Clear spring boiled sparrow tongue, live boiled dragon ball. It is a pair of couplets in Beijing Teahouse, which also has the saying that "the blue bud sparrow tongue is expensive today, and the ancient phoenix cake dragon group is expensive". "The sparrow tongue" is also a treasure in tea, and "the clear spring" is the water for making tea. The dragon figure you said is actually the "dragon group" and it also implicitly refers to tea, and running water also refers to the water for making tea. To show that the tea in his teahouse is top grade.