You documents must be attested from the foreign affairs office in your home country then it can only be processed at the embassy of the foreign affairs itself. In your case the Qatar embassy or consulate in India.

Check with the Indian Embassy in Bahrain for any other alternate. If you already had your documents attested once to come to the Bahrain, then you can utilize the same documents at the Qatari Embassy in Manama instead of traveling to your home country.