1. A method of performing a morpheme analysis using a computer, the method comprising: acquiring a morpheme analysis target and additional information associated with the morpheme analysis target, from search index data; creating, using the computer, a key based on the additional information in response to acquiring the additional information; and analyzing, via the computer, a morpheme of the morpheme analysis target by using the key, wherein creating the key comprises: creating a plurality of keys by performing the morpheme analysis for each information included in the additional information; and creating a combined key by combining the plurality of keys, and wherein analyzing the morpheme comprises: determining whether the morpheme analysis target includes a partial character string corresponding to the key; and temporarily adding the partial character string in a morpheme dictionary when the morpheme analysis target includes the partial character string corresponding to the key.