bù dāng jiā bù zhī chái mǐ guì
a person who doesn't manage a household would not be aware how expensive it is (idiom)
不
bù
no; not so
当
dāng
to be
家
jiā
home
知
zhī
to know
柴
chái
firewood
米
mǐ
uncooked rice
贵
guì
abbr. for Guizhou Province 貴州|贵州[Gui4 zhou1]