bái yún cāng gǒu
lit. a white cloud transforms into what looks like a gray dog (idiom)
fig. the unpredictable changeability of the world
白
bái
white
云
yún
abbr. for Yunnan Province 雲南省|云南省[Yun2 nan2 Sheng3]
苍
cāng
dark blue
狗
gǒu
dog