[1] In an interview, So said that the words "Kiu" (喬) and "Sing" (星) were taken from the names of his two former lovers as a memorial.
In 2007, So and Hong Kong composer Hou Guangwu participated in the CASH Pop Composition Competition, and their entry "Pink Eye Syndrome" won third place.
Since 2005, So has written song lyrics for Nicholas Tse, Jacky Cheung, Vangie Tang, Jason Chan, Elanne Kong, Ella Koon, Deep Ng, Ruco Chan, Elle Choi, Ivan Wang,Theresa Fu, Jun Kung, Eric Suen Yiu Wai, Angela Au, Sammi Chan, Terence wan, Sandy Lam and James Ng.
[1][2] In 2010, So wrote four Cantonese lyric adaptations for Jacky Cheung 's Canto-jazz album "Private Corner":[8][9] "Double Trouble", "Bu Zhi You Yuan (Lucky in Love)" (不只有缘), "Let It Go", and "Zhao Dui Ni (Which Way, Robert Frost?)"
"Bu Zhi You Yuan" by Jacky Cheung was the theme song of the Hong Kong film Crossing Hennessy.