lately I got angry with someone and discuss a lot and since there the mother of that person who actually works at my school have been spreading lies about me and the people start to doubt myself does anyone know a good spell to show people the truth without a backfire
Instead of a truth spell, which is a form of commanding spell that you would have to do on your various targets, i think an easier (perhaps) approach would be a stop-gossip/protection spell.
Google the terms "stop gossip spell" and i'm sure you'll come up with something. Alternatively search on the Lucky Mojo website. Hoodoo is full of anti-gossip spells. I'm sure you'll find something archived there/