read between the lines
US /riːd bɪˈtwiːn ðə laɪnz/
UK /riːd bɪˈtwiːn ðə laɪnz/

1.
言外之意, 領會言外之意
to understand the hidden meaning in what someone says or writes
:
•
You have to read between the lines to understand what she really means.
你必須言外之意才能理解她真正的意思。
•
His letter seemed straightforward, but I could read between the lines that he was unhappy.
他的信看起來很直接,但我能言外之意他很不高興。