Cuoi, Khamen-Boran, Kui, Kui Souei, Kuoy, Kuuy, Soai, Suai, Suay, Suei, Sui, Suoi
400,000 in Thailand (2006 Mahidol University). Few monolinguals. Total users in all countries: 452,800.
Surin, Buriram, Sisaket, and Ubon Ratchathani provinces: near Cambodian and Laos borders.
Chang (Suai Chang), Nheu, Kuay.
Literacy rate in L2: 50%. Dictionary. NT: 1978–1992.