The phrase "know nothing of" implies a lack of knowledge about something. There are various synonyms to indicate a similar meaning, such as unaware, ignorant, clueless, uninformed, and unfamiliar. All these words imply a lack of understanding or knowledge about a specific subject matter. For example, if someone says, "I am unaware of the issue," it suggests that they lack the knowledge or information about the issue at hand. Similarly, if someone says, "They are ignorant of the facts," it shows that they lack enough knowledge or information about the subject matter to make an informed decision. These synonyms convey a more precise meaning and context when used in a sentence instead of the phrase "know nothing of".