Valk,
The fields that show when you hover the mouse can be selected for each graphical object in the Planning Board Profile config.
Open the Planning board profile /n/sapapo/cdpsc0, select your planning board profile, on the left side of the screen, double click on graphical objects folder. This will list a bunch of objects. When you double click the object ID, you will see the settings to show text for that object where you can choose fields as you wish.
However, you need to know which graphical object is being used for a particular operation in the DS Board. You can dig deeper via Planning Board Profile -> Chart -> Decision table for graphical objects
Regards
AK