The word "sth" is a common abbreviation for "something" and is often used in informal writing or texting. However, there are several synonyms for "sth" that can be used to provide more specific language. Alternative phrases include "a certain thing," "an item," "a particular element," "a specific matter," or "a distinct object." Additionally, depending on the context, you may also choose to use more descriptive language such as "a piece of equipment," "a type of food," "a unique concept," or "a specific reference." By using more precise synonyms for "sth," you can enhance your writing and better communicate your ideas to your intended audience.