I think you need to specify your parameters more closely. In your original post, you talk about Indian, Muslim and Asian. Do you mean each separately or a combination? Muslims can be of any nationality. Asian people come from countries other than India and can follow any religion (or none). As well as ensuring that you gather the correct data, your diss markers will look for this level of accuracy in your dissertation.
If you mean people only of Indian (and that country only) ethnic descent, who live anywhere in the world and whose family is Muslim, then this is more likely to get the responses that you need and a better mark. Use of the broad term "Asian" may be complicating the question unnecessarily, unless you wish to include people from other ethnic descent such as Pakistani. In which case you need to specify this in your question.