1, love academics.

2. Google Academic Mirror.

3、Oalib .

4. Chinese academic journals of Hans Publishing House.

5. National Science and Technology Library.

6. hownet.

Thesis is a kind of academic writing, which is the result of systematic research and analysis on a specific topic. Usually, papers are written by scholars, researchers or students to show their research results in a certain field. Papers usually include the following main parts:

Introduction: Introduce the background, purpose and significance of the research, and put forward the research questions and assumptions of the paper.

Literature review: Review and comment on the existing related research and theories, and discuss the influence and limitations of previous work on this study.

Methods: The research methods and experimental design were described in detail, including data collection, sample selection and experimental steps.

Results: The research results were presented in the form of statistical data and charts, and the findings and data obtained in the research were presented in an objective way.

Discussion: Explain and analyze the research results, discuss the relationship between the results and research hypotheses, and compare and discuss with previous studies.

Conclusion: Summarize the main findings of this study, and further explore the future research direction and significance in this field.

In addition, a complete paper usually includes a list of references, acknowledgements and appendices to provide reference and support for other scholars' research results. The writing of papers should follow academic norms and certain writing formats, such as APA and MLA. It is an important medium for academic exchange and promoting knowledge progress, and is used to share and disseminate research results and promote academic discussion and development.