1. A method of spoken document retrieval by a system using multiple search transcription indices, the method comprising: receiving an input phrase as a search query formed of query terms; identifying a first type of query term in the input phrase, wherein the first type includes a query term in a speech recognition vocabulary of the system; identifying one or more first search transcription indices for searching the first type of query term; identifying a second type of query term in the input phrase, wherein the second type includes a query term not in the speech recognition vocabulary; identifying a plurality of second search transcription indices for searching the second type of query term; receiving at least a first list of results from the one or more first search transcription indices; receiving plural lists of results from the plurality of second search transcription indices; ranking results from a phonetic index of the plurality of second search transcription indices based on temporal proximity of phones, wherein the ranking computes a score in accordance with the following expression: score ⁡ ( k , t 0 k , D ) = 1 - ∑ i = 1 l ⁢ 5 ⁢ ( t i k - ( t i - 1 k + d i - 1 k ) ) l where k denotes a keyword having phonemes that may occur in a document transcript D at times t i k and having durations d i k ; combining first scores for a first document from the plural lists of results according to a first method to form a first combined list having a second score for the first document; combining one or more third scores of a corresponding document from at least the first list of results with the second score according to a second method different from the first method, wherein the second method comprises evaluating timestamps of words and subwords in the document to determine whether the words and subwords are in a correct order and a difference in time between adjacent words and subwords is within a threshold value, wherein the words and subwords in the document correspond to the input phrase; and outputting search results to a user based in part on the combining the one or more third scores of a corresponding document with the second score.
1. A method of spoken document retrieval by a system using multiple search transcription indices, the method comprising: receiving an input phrase as a search query formed of query terms; identifying a first type of query term in the input phrase, wherein the first type includes a query term in a speech recognition vocabulary of the system; identifying one or more first search transcription indices for searching the first type of query term; identifying a second type of query term in the input phrase, wherein the second type includes a query term not in the speech recognition vocabulary; identifying a plurality of second search transcription indices for searching the second type of query term; receiving at least a first list of results from the one or more first search transcription indices; receiving plural lists of results from the plurality of second search transcription indices; ranking results from a phonetic index of the plurality of second search transcription indices based on temporal proximity of phones, wherein the ranking computes a score in accordance with the following expression: score ⁡ ( k , t 0 k , D ) = 1 - ∑ i = 1 l ⁢ 5 ⁢ ( t i k - ( t i - 1 k + d i - 1 k ) ) l where k denotes a keyword having phonemes that may occur in a document transcript D at times t i k and having durations d i k ; combining first scores for a first document from the plural lists of results according to a first method to form a first combined list having a second score for the first document; combining one or more third scores of a corresponding document from at least the first list of results with the second score according to a second method different from the first method, wherein the second method comprises evaluating timestamps of words and subwords in the document to determine whether the words and subwords are in a correct order and a difference in time between adjacent words and subwords is within a threshold value, wherein the words and subwords in the document correspond to the input phrase; and outputting search results to a user based in part on the combining the one or more third scores of a corresponding document with the second score. 4. The method as claimed in claim 1 , wherein the one or more first search transcription indices are taken from the group of: word indices, sub-word word-fragment indices, sub-word phonetic indices, a combination of word and sub-word indices using timestamps, and a combination of word and sub-word indices using offsets.