Can we add custom language for RecognizerIntent?
I have search many SO Question like https://stackoverflow.com/questions/2080401/is-there-a-speech-to-text-api-by-google<
I don't know for sure but have you tried using RecognizerIntent?
See reference, there is a section to specify the IETF language see this section.
There is also this api demo code which you could try: http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/app/VoiceRecognition.html
I really don't know if Burmese is supported as it certainly is not listed as one of the default locales but speech recognition is different.
Have just found this project: http://code.google.com/p/recognizer-intent/ it is probably highly unlikely that Burmese will be supported out of the box but I think it is worth trying the api demo code and seeing what it says in the drop down box, good luck.
Google will unlikely support small languages any time soon. The only way to custom language is to train CMUSphinx model and use it with Pocketsphinx:
http://cmusphinx.sourceforge.net/wiki/tutorialam
http://cmusphinx.sourceforge.net/2011/05/building-pocketsphinx-on-android/