Importing sub-folders into Plex Server Library

[Enquiries]

When I import my MP4 files to the Plex Server installed on my Synology 1821+, they emerge as individaul files in the library ie withouy the subfolder which has the composer's name and (within that) the sub-sub-folder with the type of composition etc. It will be extremely tedious to import each sub-foldeer individaully. Is there any way I can import all nested sub-folders into the Plex Library?