1. A directional selling apparatus, comprising: a microphone array having a plurality of microphones, each microphone importing an input sound; a voice recognition unit configured to detect a certain keyword included in a sound signal based on the input sound and set a directional determination period based on an occurrence time of a sound signal corresponding to the certain keyword; a directivity detector configured to detect a direction of the input sound in the directional determination period and output the detected result; and a directivity setting unit configured to set a directivity of a prescribed apparatus based on the detected result of the directivity detector, wherein the voice recognition unit recognizes a keyword different from the certain keyword for releasing the directivity set by the directivity selling unit and outputs a directivity release signal; and the directivity setting unit releases the directivity of the prescribed apparatus when the directivity release signal is supplied from the voice recognition unit.