read between the lines

Meaning: 空気を読む、言葉の真意を理解する

For Example:

‣ My mother said she's doing well, but reading between the lines I don't think she's doing all that well.

お母さん元気にやっとるでって言うてたけど、ほんまはあんまり元気にやっとらんと思うんよ。

‣ When we listen to others, we should try to read between the lines before we say something that might hurt him or her.

他人の話に対して言葉を返す時は、その人の真意をしっかり考慮した上で、返さなあかん。

Synonym:

guess

surmise