The term 'ซึ่งไร (sʉ̂ng rai)' is commonly used in Thai to refer to any one or any part of something or someone, similar to 'which' or 'whatever' in English. It can be used in questions and statements as a placeholder for an unknown or unspecified element. You use 'ซึ่งไร (sʉ̂ng rai)' to indicate an open selection among a set of possibilities or options.