When you import or save new references to Mendeley, they are saved in the "All Documents" folder, unless you choose a destination folder using the Save to Mendeley menu.
Default location
Save into a specified folder
CREATE A FOLDER
SAVE A REFERENCE INTO A FOLDER
EDIT IN MENDELEY DESKTOP
EDIT IN MENDELEY ONLINE
Mendeley Desktop provides enhanced features for working with PDFs. Highlight, annotate, and add notes to documents. These notations are searchable in the desktop application.