Is there any way to use embedded fonts?

Hi, I'm new here & I would like to know the following: is there any way to use the embedded fonts when converting formats?
I.E. I create all starting e-book documents by scanning the book using Omnipage 18 & creating a .RTF document copy which I then format. I try to use a matching Font to the original book especially matching any chapter title fonts as close as possible. But when I add the book to Calibre & convert it to .epub or .mobi the fonts from word are all converted to Times New Roman (Ugh! which I hate). I know I can change the font family Calibre uses but I want to know if there is any way to use the actual fonts from the .RTF doucument when converting? please let me know.