Spotlight will index what you specify in Spotlight Preferences. If the category is not shown, it is not available to be indexed. There is nothing wrong with using EasyFind for those.
If you have reason to believe the Spotlight index is incomplete or corrupt force it to rebuild its database according to the instructions here.
I've found many people often call the Mac Pro a "G5" because it's (still) the same design.
As for the question, you can try opening the Spotlight system preferences and adding your hard drive(s) to the Privacy list, followed by immediately removing them. This will force the system to rebuild the Spotlight index and hopefully make finding files work better.