Zotero - overview of files

I use Zotero to organise articles and books. Within Zotero each file is saved in a separate folder with a unique nme of undecipherable strings of digits.

I would like to be able to browse all files as in one long list. One way could be to copy all those files from a number of subfolders to one other folder. Another way could (I suppose) be to browse a folders sub and sub-subfolders while ignoring these, only showing the actual files.

Which is possible and preferable?