1. A method for adapting a language model to a specific environment, the method comprising: receiving, by a processor, a plurality of interactions captured in the specific environment; retrieving, by the processor, a plurality of external documents based on a plurality of query expressions, wherein query expressions are generated by applying a topic detection algorithm on textual transcripts in order to detect the different topics discussed in the plurality of interactions; generating, by the processor, an external corpus by selecting documents from the documents retrieved; detecting in the external corpus terms related to the environment that are not included in an initial language model; and adapting, by the processor, the initial language model to include a plurality of the terms detected.