http://www.roc-taiwan.org/PH/ct.asp?xItem=409174&ctNode=4712&mp=272

The nationals of India, Thailand, Vietnam, the Philippines and Indonesia, who possess a valid visa (including an electric one) (**) or permanent resident certificate issued by U.S.A., Canada, Japan, U.K., Schengen Convention countries, Australia or New Zealand, are eligible for the visa exemption program, which permits a duration of stay up to 30 days. Those who meet the above qualification and have never been employed in Taiwan as blue-collar workers have to apply to the “Advance Online Registration System for the Visitors of Nationals from Five Southeast Asian Countries to Taiwan” of the R.O.C. National Immigration Agency (website: https://niaspeedy.immigration.gov.tw/nia_southeast/) for an “Authorization Certificate” before coming to Taiwan. After completion, the printed-out Certificate can be used by the foreign visitor for boarding the airplane and the immigration inspection.