[1] She started writing young and by age 21, had published her first short story, "Room 27" (Indonesian: Kamar 27).
It was followed by her first book in 1969, a children's story titled My Home is My Castle (Indonesian: Rumahku adalah Istanaku).
In 1972 she followed Karmila's success with The Storm Will Surely Pass (Indonesian: Badai Pasti Berlalu), which was serialized in Kompas between 5 June and 2 September 1972, with a novelized version being published in 1974.
She also published some collections of short stories, including Love Song (Indonesian: Lagu Cinta) and Monik.
[5] In 2004, Tjoa published A Bud of Hope (Indonesian: Sekuntum Nozomi) to commemorate the eighth anniversary of the 1998 Jakarta Riots.