Direct search, when we know the title of the target document, ISBN/ISSN, or DOI, we can directly search in the search box.

Google Academic, also known as Google Academic, is a free academic search engine developed and held by Google. Note that unlike HowNet, it is free. Google Academic includes most published academic journals in the world. In addition to the most common journal articles, Google Academic can also help users find various academic documents, including papers, books, preprints, abstracts and technical reports.