Can't restore files from online assets

In my online assets, there are lots of files that get sent to deleted. These are not old files or ones that we haven't used lately. It wasn't a big deal as long as I could restore them. I searched for a file today, found it, but when I clicked it, I got an error message that "the cloud document is currently unavailable."

It shows the document in the search results and even flashes it on the screen like it's going to open before this error comes up.

I sat in a chat with a rep about this a while ago, but it hasn't gotten fixed. I either need a way to keep files from getting deleted or to be able to restore them.