Search room introduction: Search room is a body search place set up to prevent detainees from hiding sharp weapons and resisting. Every morning, the detainees come here and are forced to take off their prison clothes, step over a wooden bar, open their mouths in front of the guards, and are searched by the guards. After being searched, they put on prison clothes and go to the factory to serve, twice a day, morning and evening, all year round. Every day. The prison uniforms were divided into red and blue, which was a method used by the Japanese colonial administration to create divisions among the prisoners.