I found, that I have much too many subfolders. So it seems to be nice, to use folders and tags. It seems not to be possible.
Either I have the folder-view or the tag-view.
I like to mark 34 documents with a tag. How can I do that? It seems, I can only perhaps mark 2 file at the same time, but noch 34.
You can view tags in all views and select its documents afterwards. In the non tag views (e.g. 3-pane or columns) just navigate into the “Tags” group.
To tag multiple selected documents, e.g., from a Search results list:
Choose Tools > Show Groups & Tags.
In the Groups & Tags panel, open the Tags group to display the desired target tag.
Drag the selected documents into that tag group in the Groups & Tags panel.