1. A content management device for managing acquired content in a searchable manner, the device comprising: a storage device that stores a search database in which a plurality of keywords and content are registered; a registration unit that registers new content in the search database; and a search unit that searches content registered in the search database, wherein the registration unit performs operations comprising: extracting a plurality of keyword candidates associated with the new content from the search database; displaying the extracted keyword candidates; and registering a keyword candidate designated from among the displayed keyword candidates in the search database, as a search keyword in association with the new content, and wherein the search unit performs operations comprising: displaying a plurality of search keywords registered in the search database; extracting content associated with a search keyword designated from among the displayed search keywords from the search database; and displaying the extracted content.