There are numerous synonyms you can use instead of the phrase "contributes to." Some of the most common synonyms include enhances, promotes, facilitates, fosters, stimulates, supports, augments, bolsters, nurtures, boosts, strengthens, and aids. Each of these words has a slightly different nuance, but they all convey the idea of helping something to grow, succeed, or improve. When you want to express the positive impact of a particular action or element, these synonyms can be useful to help you avoid overusing the same phrase and add variety and interest to your writing. Try experimenting with different words to see which ones work best for your specific context and audience.