I was arrested in 2010 in S. Dakota for possession of drug paraphernalia, and Ingest Intoxicant other than alcohol. Am I able to have this expunged?

In 2010 I was driving from back home to New York from Washington on I 90. I was pulled over for speeding. The office searched my car and found a small amount of marijuana and a pipe. I was arrested and charged. I paid bail and hired an attorney and left South Dakota the next day. I currently am a teacher working in Shanghai and plan to move to Hong Kong. I recently had an FBI back ground check so I could apply for my teaching license and saw that these charges appear. I would need to present a FBI background check to apply for a working visa in Hong Kong and would like it clean. I have had no arrests since this time.