The phrase "inquire into" refers to investigating or looking into something in order to gather information or understand it better. Synonyms for this phrase may include "investigate," "examine," "probe," "inspect," "explore," "scrutinize," and "search." Additionally, "look into," "query," "question," "interview," "interrogate," "analyze," and "assess" can all also be used as synonyms for "inquire into." These words can be useful in creating depth and specificity in writing and communication, allowing for more descriptive and precise language when discussing investigations or research.