Her popularity boomed in the 1970s after her success in Japan. By now singing in Mandarin, Cantonese, Japanese and English, Teng's influence spread to Malaysia and Indonesia. In Taiwan, she was known not only as the island's most popular export, but as "the soldier's sweetheart" because of her frequent performances for servicemen. Teng was herself the child of a military family. Her concerts for troops featured Taiwanese folk songs that appealed to natives of the island as well as Chinese folk songs that appealed to homesick refugees of the civil war. She gave many free concerts to help the less fortunate or to help raise funds for charities.