How could I download the full MFN database?

I am interested in the detail of MFN database (the difference between KEGG), but I can not find the download link of full MFN database. Could you help me?

I would assume you are using MetaboAnalystR: if you perform analysis using MFN, a copy of the library (hsa_mfn.qs) will be saved in your local directory. You can inspect it using RStudio. Note this is not possible using web interface which is not designed for such purpose.