2. The method as claimed in claim 1 , wherein the voice information comprises pronunciation information of text converted through voice recognition of the uttered voice.
3. The method as claimed in claim 2 , wherein setting the similar word satisfying the predetermined condition comprises comparing a reliability value for each of the plurality of similar words and a critical value for each of the similar words and setting a similar word having a reliability value higher than the critical value for each of the similar words as the target word.