Is there no other way to do things other than stealing? India's space program goes back to the late 60s. When faced with technology sanctions from the United States, they studied up the fundamentals, researched by trial and error and learnt from the mistakes and sucesses of other bigger space organizations. They know their limits, in terms of budget and governmental support. But they've persisted and continuously pushed their own limits, come up with the most efficient ways of achieving missions. Ex, Mangalyaan, Chandrayaan 1 and now the Chandrayaan 2. India has even launched a constellation of its own Positioning System of Satellites, the IRNSS, which is yet to be comissioned into public use.

In short, ISRO has simply learnt to be efficient and adaptive. Relied extensively on first principles and fundamentals. It is an really inspiring story of ingenuity and innovation. More "discovered and developed" than "acquired".

Intellectual property rights lasting more than a short time are theft from humanity. Their ostensible reason to exist is to contribute to our shared cultural inheritance, and yet.

Why are you assuming that Indian scientists and engineers cannot develop things themselves? That is bad faith.

Chinese scientists and engineers can also develop things themselves, then why are they accused of stealing technology often? If something is possible doesn't mean it's the best option they've on hand.

To answer your question specifically, certain design elements were licensed from other countries, before being largely indigenized. For example, the Vikas engines were initially developed in the 70s, from Ariane's Vulcan engines. This family of engines powers the second stage of the current mission.

Cryogenic engines were initially bought from Russia, but economic sanctions in the late 90s-mid 2000s forced India to develop its own indigenous cryogenic engines. These were based on the Russian models the Indian engineers were already familiar with, though it delayed the development of India's space program by at least a decade.

Are you even a scientist that you are talking about dynamics of exchange of technology? I mean are you qualified enough to talk like this? Just asking in good faith

No I am not qualified, neither I am scientist. And probably, that's why I am curious