1. An apparatus for searching for position information, comprising: a Space Of Interest (SOI) data base (DB) including a plurality of space object SOIs and relationship objects; a search input unit configured to receive at least one of the plurality of space object SOIs and a search word from a user; a relationship display unit configured to output at least one relationship object with respect to the received at least one space object SOI; a relationship selection unit configured to receive a selection for a portion of the output relationship objects from the user; a search processing unit configured to perform searching on the SOI DB based on the selected relationship object, the received space object SOI, and a search word; and a search output unit configured to output a searching result for the searching, wherein the relationship object indicates a relationship, which has been previously defined on the SOI DB, between the received space object SOI and a space object SOI related to the received space object SOI among the plurality of space object SOIs.