Singer Sapna Awasthi, known for 'Chaiyya Chaiyya' song from 'Dil Se', said Shah Rukh Khan has been very lucky for her career. "Unke gaane gaake toh humari life chal rahi hai (I'm surviving life by singing his songs)," she added. "I'm thankful to AR Rahman and Gulzar ji for giving me such a big hit song," Sapna told Bollywood Thikana.