1. A method for retrieving keyword from speech, comprising: configuring, by an apparatus comprising a processor, at least two types of language models in a model file, wherein each type of language model comprises a recognition model and a corresponding decoding model; extracting, by the apparatus, a speech feature from to-be-processed speech data; performing, by the apparatus, language matching on the extracted speech feature by using recognition models in the model file one by one, and determining a recognition model with a highest language matching rate; determining, by the apparatus, a decoding model corresponding to the recognition model with the highest matching rate from the at least two types of language models; decoding, by the apparatus, the extracted speech feature by using the determined decoding model, and obtaining a word recognition result after the decoding; and matching, by the apparatus, a keyword in a keyword dictionary and the word recognition result, and outputting a matched keyword.