— In this paper, we propose a powerful and convenient querying model, "Queryball", for users to query in immersive VR systems. In immersive VR systems, users expect intuitive and heuristic interactive operations derived from empirical knowledge in the real world. As a possible method for the interactive operations, interaction by virtual tools has been proposed. However, intuitive and heuristic query interaction by virtual tools is too difficult to be performed, because query interaction in immersive VR systems cannot be represented as concrete virtual objects. Queryball is a new style of querying model for intuitive and heuristic query interaction. Queryball, which is a translucent ball, is defined as a quadruple of area specification, search condition, and two types of display methods. The search condition can be applied only to the virtual objects inside of the Queryball. The query results are shown to the user according to the display method. The position and radius of ...