DISPLAY DEVICE, SERVER DEVICE, VOICE INPUT SYSTEM AND METHODS THEREOF

A server apparatus is disclosed. The server apparatus includes a communicator configured to receive a text which corresponds to a voice signal input, and a controller configured to, in response to a keyword, which corresponds to the text, not existing from among a keyword included in a mapping table, search for content information belonging to at least one content genre mapped with a synonym of the text, provide a search result to a display apparatus through the communicator, and update the mapping table by adding the synonym as the keyword. Accordingly, the server apparatus may effectively perform search for content information according to voice input.