You can choose Science Network, EBSCO, springer link, etc. Database navigation from the school library website. If you are not in school or have graduated, you can also use Ai Xue or onacademic to download foreign documents.

Thesis:

Thesis is a Chinese word, and its pinyin is lùn wén, which is a common word in classical literature and refers to conversation or exchange of ideas. Nowadays, papers are often used to refer to articles that conduct research in various academic fields and describe academic research results, which are referred to as papers for short. It is not only a means to discuss problems in academic research, but also a tool to describe academic research results in academic exchanges. Including academic papers, graduation papers, dissertations, scientific papers, achievement papers and so on.