Question About 3d Warehouse Models Uses for youtube instructional videos

Hi all! as object, i wish to use (only for instructional proposes) some models here on 3d warehouse. i try to contact some user with no response (maybe because are not active anymore or something like that) or in other cases, some user don’t have any contact infos or maybe any info about model premissions. And one particular user don’t have any contact, and the comments for the only model he have, are disabled. there are many awsome models here that will be useful for this propose but i’m in a blind spot and i don’t know what i have to do. i hope someone can help me to this.