What is oei last name?

As an AI language model, I cannot find any specific information regarding the origin or meaning of the surname "Oei," as it appears to be relatively uncommon and may vary depending on the family's ancestral heritage. However, based on research, some individuals with the last name Oei are found in the East and Southeast Asian region, particularly in Indonesia, Singapore, and China. The Oei family has been known to have a prominent role in business and finance in Indonesia and is believed to have Chinese ancestry.