For downloading foreign documents, you can use Google academic search to obtain relevant information of documents, such as document DOI number, document source database name, etc. A few documents in Google Academic can be downloaded directly, and those that cannot be downloaded directly can be copied to sci-hub for retrieval and download. It should be noted that documents from 2022 and beyond should not be used in sci-hub, because sci-hub has not been included.

Documents that cannot be downloaded by Google Academic and sci-hub can be retrieved and downloaded from the document source database. If you don't have the resources of the document source database, you can use the document party downloader (wxdown.org) to enter the database for retrieval and download.

For example, the following documents in 2022, Google Academic and sci-hub, cannot be downloaded and are included in the IEEE database.

Solution: Double-click the name "IEEE" in the literature download database to enter the database:

Enter the IEEE database and directly input the title of the article to retrieve the literature;

To retrieve the literature, click PDF to download the full text:

This document that Google Academic and sci-hub can't download is downloaded as follows:

If you need resources from other literature sources, you can use the literature download device. You can double-click the name of the database to be downloaded in the resource library and enter the database to retrieve the downloaded literature.

Commonly used foreign literature databases are:

Science Network is an important database for obtaining global academic information, among which SCIE, SSCI, A & amp； Citation index databases such as HCI, JCR journal citation reports and ESI essential science indicators are well-known in the scientific and educational circles all over the world.

Sciencedirect: a world-renowned academic periodical publisher in the Netherlands, which publishes a large number of academic books and periodicals every year, most of which are included by SCI, SSCI and EI, and is internationally recognized as a high-grade academic periodical.

ProQuest full-text dissertation database: it is the most comprehensive and high-quality database in China, and the only one that can comprehensively query the full text of foreign dissertations.

SpringerLink: It is the world's largest online academic resource platform in the field of science, technology and medicine (STM). Springer e-book database includes various springer book products, such as monographs, textbooks, manuals, atlases, reference books and series.

PubMed is a free search engine that provides a database of biomedical papers and abstracts. PubMed information does not include the full text of journal articles, but it can provide links to full-text providers (paid or free).