They do use cockroaches in china. Its becomming a thing. Theres a good marketing campaign for you.
Saw one at the farm a few weeks ago. Ive seen almost none my whole time here but have always been told they are easy to find here compared to other countries. No tips sorry. The one i saw ran into the juniper farm near our farm farm so theres something in there it likes. Probably likes the no hunter aspect anf no traps being a farm.