SBS's "Secret Garden" OST has not only been dominating music charts, but it's also been selling like hotcakes! Sales for the OST have been so great that they no longer have any copies left to sell.  The OST consists of two parts, which contains Baek Ji Young's "That Woman" and Kim Bum Soo's "Appear."  CD1 has already released 30,000 copies and additional orders are still pouring in. CD1, which consists of 4men's "Reason" and Sung Shi Kyung's "You're My Spring," had 30,000 pre-orders before its release on January 3rd. For three months, every song off the OST grabbed high digital sales as well chart rankings; they've also earned popularity overseas as well. A representative of Sony Music commented, "This isn't simply just an OST, but something exceptional even in the music industry.  Fans can look forward to CD5, which contains Hyun Bin's 'That Man.'" Source + Photos: Sports Chosun via Daum