Version: 4.2.8.2
Build ID: 420m0(Build:2)
I want to create folders on different subjects, into which I can save relevant documents
Do you know how to use your OS file-system?
LO Tools>Options>LibreOffice>Paths will show the path to the Directory where LO Documents will be saved. You can create Sub Directories here with your Operating System. When you save a Document the pop up will default to the Directory indicated in the Path. If you have already created Sub Directories here you can select that Directory. If you have not created Sub Directories then in the save pop up click at the top right “Create New Folder” to create a new directory.
Yes, this sounds like a file system issue rather than a LibreOffice issue.
You should be able to quit LibreOffice, create the folder, and drag-and-drop files into that folder in most systems including many Linux environments, OS X, older Windows, etc. It may be harder in Unity, iOS, etc.