Due to U.S. copyright law, citations management tools like Mendeley often do not import full text files along with references. Attaching the full text file to the reference is similar to attaching a file to an email:
When add references to Mendeley, keep in mind that importing references into your Mendeley account may not bring any available full text file with it. You may have to download the full text separately and then attach the file to the reference.
It's also a good idea to synchronize your Mendeley account after adding references.
The Web Importer is an extension for your web browser that lets you import references from sources that do not have a clear way to export references. You can download the Web Importer from the Tools menu in your Mendeley Reference Manager. Once you download the Web Importer, you should see a little Mendeley icon in your browser's extensions. If you use Google Scholar frequently, you may wish to bookmark the Web Importer. Here's how it works:
Your Mendeley account includes access to the Mendeley Search. Mendeley Search is a crowdsourced library of references identified in millions of Mendeley accounts. All Mendeley Search results are anonymized and no user data is shared.
Sometimes you may need to create a reference from scratch. To do this, you should create a reference manually.
Some citations may have an identifying code in the citation. Examples of these codes include a digital object identifier or DOI, a PMID or PubMed ID, or an ArchiveX ID. You can use these codes to import a reference into Mendeley.
Use the +Add New button to add a file or a folder of files to Mendeley. Select +Add New, select File(s) from computer and then browse to the file you with to import to Mendeley.
You can add papers or articles to Mendeley by dragging and dropping a PDF into the Mendeley Reference Manager window. Mendeley will automatically extract the metadata from the file to create a reference for that file.
Keep in mind the quality of the reference depends on the quality of the file metadata. If you drag & drop a scanned article -- one that was scanned using a photocopier -- that file will not have any metadata to create a reference.