DT isn't "seeing" certain types of files

just downloaded DT.  Imported my entire home directory.  when I do searches DT apparently is ignoring any of my documents that are not .txt, .pdf or .doc files.  It’s not seeing content in excel spreadsheets, and it’s not even seeing these file names?  If I search on the file name of a spreadsheet file it comes back dry.

Am I doing something wrong or does DT only ‘see’ certain types of files? I figured once I imported them they were there.

ok, reviewed the Help section of supported file types and see that it’s text and image based so I ‘get’ that DT doesn’t see the contents of my spreadsheets, mindmaps, etc…, but why doesn’t it see the file names?  it should do this, right?

As DT will probably never support proprietary file formats, just turn on the preference to create links to unknown files and you’ll be able to search for file names (or imported Finder comments).