An example device for transmitting an answer message includes a display configured to display information, a communicator configured to receive a question message from another device, a processor configured to control the display to display graphics representing a plurality of pieces of recommendation information which are includable in an answer message for the received question message and relations between the plurality of pieces of recommendation information, and a user input unit configured to receive a user input that selects at least one of the plurality of pieces of recommendation information, wherein the communicator is further configured to transmit an answer message including the selected recommendation information to the another device according to the user input.