I think you'll need to ask Indian embassy, how to apply for another visa. And where can you apply. I'm not sure how easy that will be if you're in Thailand.
Youre not Indian but entered India on single entry student visa? Then left to go to Thailand or want to go to Thailand. Then return to India? Maybe explain a bit better because it's a bit confusing.
There isn't a visa on arrival for Australian passport. They are given an exemption and enter for 30 days with no visa. This can be extended for extra 30 days at immigration.