List documents by title not pictures
Hello,
If you are talking about the thumbnails shown in the right pane of LibreOffice Start Center - sadly the answer is: Not at all - there is no way to order them. They appear on a recently used basis (last used - first shown). In that sense: They are not shown “by picture” but “by last used”.
If you want to see your documents listed in alphanumerical order, just use your operating system’s File Manager. Double click on the name of the document that you wish to open, and LibreOffice will open it.
(Unless of course, you are using Microsoft Windows 10, in which case you must deal with file permissions and all that that entails.)