Hi Patsy,
Not all our products have BIM/CAD files, but when you do a search you can filter them by the file you are looking for. Simply enter a product type in the search bar (or leave this blank if you want to see everything) and hit the search icon. Once the search is loaded, you will see a 'Formats' filter on the left hand side. Tick the file you are after (or 'Other 3D' if your preferred file type is not there) and you will only see products that have those files attached.
I hope that makes your search easier!