I think you can use a veracrypt mount in the cloud. Your files should be searchable locally if you mount it. You can have some simple search capabilities especially if you store them or put tags in the filename itself and have a sane folder system in place.
One downside I can think of is that the system is inefficient and causes you do download the whole thing instead of just the files you need. This is doable if the total file size is reasonably small and you have a fast connection. You can split the veracrypt into smaller chunks but you have to have a good way of separating files in your system.