15. The non-transitory, computer-readable medium of claim 14 , wherein the call information further includes a voiceprint of the telephone conversation, and wherein the one or more processors is configured to index the call information by indexing the call information based on the one or more keywords, a frequency of the one or more keywords, and at least one stress feature identified in the voiceprint.
18. The non-transitory, computer-readable medium of claim 15 , further storing instructions that, when executed by the processor, perform operations comprising: assigning a weight to each of a plurality of keywords; weighting the one or more identified keywords based on the assigned weights; and indexing the call information based on the weighted keywords.