Apart from the dossier Chessbase 10 offers another way for you to prepare to play against a particular player.
Open the player index in a database list and select the player against whom you want to prepare yourself.
Right clicking on a player’s name opens a context menu that offers amongst other things the options Prepare against White and Prepare against Black.
The same information is displayed as in the Opening Reference. The contents of the display have to do with the white and black repertoires of the selected player.