There are several synonyms for the phrase "buried in" that you can use depending on the context of your sentence. Some of these synonyms include engulfed, immersed, inundated, and swamped. Engulfed is often used to describe something hidden or completely covered by something else. Immersed is used to describe being fully involved or absorbed in something. Inundated is used when something is flooded or overwhelmed with a large amount of something. Finally, swamped describes being overloaded or overburdened with work or tasks. By using these synonyms for "buried in," you can add variety and depth to your writing.