I’ve downloaded collada file from 3d Warehouse because I run older version of sketchup on my PC. So when I try to import the file the object is completely covered in meshed surfaces which takes a Lot of time to select and delete.And it looks something like this
Thanks for you answer. But if a component has many sub components and groups inside it(like a vehicle I attached above) I need to select each and every surface and then soften it. And this takes a lot of time.