There are numerous synonyms for the phrase "not have it," which means to lack something or be unable to do something. One common synonym is "be missing," which implies that the item or skill in question is absent or unavailable. Another option is "be deficient," suggesting that one is lacking to some degree and needs to make up for the deficit. Other synonyms include "fall short," "come up empty-handed," and "be out of luck." Each of these phrases can be used to describe situations in which someone is unable to achieve their desired outcome due to a lack of resources or abilities.