have no idea of how things stand; not know the true state of affairs;not sure of (oneself)
? 一切都是胸中無“數(shù)”，結(jié)果就不能不犯錯誤。(《毛澤東選集》1380) They have no“figures”in their heads and as a result cannot help making mistakes.
胸中無數(shù)xiōnɡ zhōnɡ wú shù
比喻對情況不了解，心里沒有底。not to know what’s what, not know for certain, feel unsure of sth.