How to extend your stay by studying abroad at your own expense?

1. Apply for extension of student visa: If your doctoral program is not over yet, you can apply for extension of student visa to the local immigration office to extend your stay.

2. Apply for a work visa: If you have completed your doctoral degree, you can try to apply for a work visa. Some countries have special visa policies for doctoral graduates, such as Tier2 visa in Britain and 485 visa in Australia.

3. Apply for investment immigration: Investment immigration programs in some countries allow you to obtain permanent residency through investment or entrepreneurship. This requires you to have certain funds and business plans.

4. Apply for skilled migration: If your major is in short supply, you can try to apply for skilled migration. Some countries have special visa policies for technical talents, such as ExpressEntry in Canada and SkillSelect in Australia.