"See into" is a phrase used to describe the act of gaining insight or understanding about something or someone. There are several synonyms for this phrase that can be used in different contexts. The word "perceive" can be used to mean to "see into," or gain insight or understanding about something or someone. Another synonym is "discern," which means to recognize or understand the true nature of something. "Comprehend," "grasp," and "fathom" are also synonyms for "see into." All of these words can be used interchangeably to describe the act of gaining insight or understanding about something or someone.