海水不可斗量

see 人不可貌相，海水不可斗量[ren2 bu4 ke3 mao4 xiang4 , hai3 shui3 bu4 ke3 dou3 liang2]

surname Hai

ocean / sea / CL:個|个[ge4],片[pian4] / great number of people or things / (dialect) numerous

seawater

surname Shui

water / river / liquid / beverage / additional charges or income / (of clothes) classifier for number of washes

no; not so / (bound form) not; un-

cannot / should not / must not

cannot; should not; must not

can / may / able to / to approve / to permit / to suit / (particle used for emphasis) certainly / very

used in 可汗[ke4 han2]

abbr. for the Big Dipper constellation 北斗星[Bei3 dou3 xing1]

dry measure for grain equal to ten 升[sheng1] or one-tenth of a 石[dan4] / decaliter / peck / cup or dipper shaped object / old variant of 陡[dou3]

to fight / to struggle / to condemn / to censure / to contend / to put together / coming together

variant of 鬭|斗[dou4]

variant of 鬥|斗[dou4]

variant of 鬥|斗[dou4]

to measure

capacity / quantity / amount / to estimate / abbr. for 量詞|量词[liang4 ci2], classifier (in Chinese grammar) / measure word

you can't judge a person by appearance, just as you can't measure the sea with a pint pot (idiom)