“Unsweetened” is a subclass of “no sugar added” though, and so if you’re really looking for “unsweetened”, you still have to read the labels of all of the “no sugar added” products that chose that (more generic) label over the (more specific) “unsweetened” label.
No sugar added should mean no sweeteners added, but that’s not the case unfortunately.
“Unsweetened” means no sweeteners added. “No sugar added” means no sugars, but maybe other sweeteners.
“Unsweetened” is a subclass of “no sugar added” though, and so if you’re really looking for “unsweetened”, you still have to read the labels of all of the “no sugar added” products that chose that (more generic) label over the (more specific) “unsweetened” label.