A cloud server including a communication interface; and at least one processor configured to: detect a plurality of IoT devices connected to the cloud server from the communication interface, based on detecting the plurality of IoT devices connected to the cloud server, determine that the plurality of IoT devices are equipped with a corresponding plurality of intelligence engines, read and store a plurality of intelligence engine types of the plurality of intelligence engines, obtain a plurality of online states of the plurality of IoT devices, receive a search instruction sent from a receiving IoT device of the plurality of IoT devices, identify an instruction type of the search instruction, and store a correspondence between the instruction type and a preferred intelligence engine type, and select an IoT device based on the correspondence.