Read between the lines
Definition 1 of 1
Pro Tip 1/3Subtle Clues
Look for small hints or indications that reveal the true message or emotion. 
She smiled, but reading between the lines, I sensed she was upset.
Pro Tip 2/3Context Matters
Consider the situation and background to better grasp the hidden meanings. 
His praise seemed sincere, yet reading between the lines, it was sarcasm.
Pro Tip 3/3Unspoken Words
Pay attention to what is not said directly but might be implied. 
The note was cheerful, but reading between the lines, she was lonely.