1. An apparatus comprising a non-transitory storage medium storing a software module for searching for position information, the software module 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˜ wherein the relationship display unit represents at least one relationship object and the space object SOI connected to the received space object SOI by the at least one relationship object in a relationship graph structure on the basis of the received space object SOI, and wherein when information for a relationship object included in the specific SOI in the relationship graph structure and a related SOI is selected, the relationship graph structure is again displayed on the basis of the specific SOI.