In the present invention, a method for searching multilingual keywords in mixlingual speech corpus is proposed. This method is capable of searching audio as well as text keywords. The capability of audio search enables it to search out-of-vocabulary (OOV) words. The capability of searching text keywords enables it to perform semantic search. An advanced application of searching keyword translations in mixlingual speech corpus is also possible within posteriorgram framework with this system. Also, a technique for combining information from text and audio keywords is given which further enhances the search performance. This system is based on multiple posteriorgrams based on articulatory classes trained with multiple languages.