2. Make a list of overseas experts in this major.
3. Take some notes on your list of overseas experts, because now you only have the professor's name, school unit (laboratory), email address, etc. And you have to make some comments on the professor you want.
4, the mail problem, first of all, gmail, Hotmail, yahoo (the United States, not China), I have always recommended gmail, I feel very easy to use (mentioned below). Generally speaking, it is enough to send 5- 10 letters a day. You can use a simple "query" as the title, and so on. Maybe, about a month, I said maybe, maybe overseas professors of your major all over the world asked you to contact one.
5. Accept the offer.
A postdoctoral fellow refers to a person who engages in scientific research in an institution of higher learning or research after obtaining a doctorate, usually in a postdoctoral mobile station or a postdoctoral research center. It should be noted that postdoctoral fellows are not degrees, but work experience.