Meaning: The writer's words made the readers feel strong emotions.
Choice of Words: "Writer's" refers to the person who wrote the words. "Words" are the basic units of language. "Touched" means to move or affect someone emotionally. "Readers'" refers to the people who read the words. "Hearts" refers to the center of a person's emotions. When we say "Writer's words touched readers' hearts," we mean that the writer's words made the readers feel strong emotions.