First of all, you should choose the core words related to your major. If the result of a keyword search is not good, you can search with another keyword with the same meaning, which is synonymous conversion. Sometimes Chinese keywords are not easy to search, so you can try to search with English words. If a keyword can't solve the problem, you can use multiple keywords (that is, the combination of keywords) to search together and use logical relations to search. If it is not good, you can use advanced search, so the probability of success is greater. Google's advanced search is being set-> advanced search.

Baidu's advanced search needs to enter "Baidu Search" in the input box.

Finally, you can try command search. Common commands:

Limit the search scope to the title of the web page.

The title of a web page is usually a summary of the content of the web page. Sometimes, you can get good results by limiting the query content to the title of the web page. The usage method is to use "intitle:" to guide the particularly critical part of the query content.

For example, to find a photo of Brigitte Lin, you can query it like this: Photo Title: Brigitte Lin.

Note: There should be no space between the integer: and the following keyword.

Restrict the search to a specific site-site.

Sometimes, if you know that there is something you need to find in a certain site, you can limit the search scope to this site to improve the query efficiency. The usage method is to add "site: site domain name" after the query content.

For example, the software downloaded by Skynet is good, and you can query it like this: msnsite: skycn.com.

Note that the site domain name followed by "site:" should not be "http://"; In addition, there should be no space between site: and site name.

Limit the search to url link -inurl.

Some information in the url of a web page often has some valuable significance. Therefore, if you make some restrictions on the URL of search results, you can get good results. The way to achieve this is to use "inurl:" followed by keywords that need to appear in the url.

For example, if you want to know how to use photoshop, you can query it like this: photoshop inurl:jiqiao.

"photoshop" in the above query string can appear anywhere on the webpage, and "jiqiao" must appear in the webpage URL.

Note: inurl: There should be no space between the grammar and the following keywords.

Exact match-double quotation marks and book titles

If the input query words are very long, the query words in the search results given by Baidu analysis may be split. If you are not satisfied with this situation, you can try to make Baidu not split the query words. This effect can be achieved by adding double quotation marks to the query words.

For example, if you search Shanghai University of Science and Technology without double quotation marks, the search results will be split, and the effect is not very good. But if you add double quotation marks, the scores of "Shanghai University of Science and Technology" will all meet the requirements.

The title of the book is Baidu's unique special query grammar. In other search engines, the title will be ignored, while in Baidu, you can query the Chinese title. Using the query words of the title of a book has two special functions. First, the title of the book will appear in the search results; Second, the content of the title extension will not be split. The title of a book is particularly effective in some cases, for example, to find movies or novels with popular and commonly used names. For example, if you look up the movie "Mobile Phone", if you don't add the title, it is often a communication tool-mobile phone. After adding the title, the results of "mobile phone" are all about movies.

Require that the search results do not contain specific query words.

If you find that there is a certain type of pages in the search results that you don't want to see, and these pages all contain specific keywords, then you can use the minus sign grammar to remove all these pages containing specific keywords.

For example, I searched for the condor heroes, hoping it was about martial arts novels, and found many web pages about TV dramas. Then you can query like this: condor heroes-TV series

Note that there must be a space between the preceding keyword and the minus sign, otherwise the minus sign will be treated as a hyphen and lose its grammatical function. There is no space between the minus sign and the last keyword.

Professional document search

A lot of valuable materials are not ordinary web pages on the Internet, but exist in Word, PowerPoint, PDF and other formats. Baidu supports full-text search of Office documents (including Word, Excel and Powerpoint), Adobe PDF documents and RTF documents. To search for such documents, it is very simple to add a "filetype:" document type qualifier after ordinary query words. "Filetype:" can be followed by the following file formats: DOC, XLS, PPT, PDF, RTF, ALL. Where ALL means to search all these file types. For example, refer to Zhang Wuchang's economic paper on transaction costs. "Zhang Wuchang filetype:doc", click the title of the result to download the document directly, or click the "HTML version" after the title to quickly view the document content in web page format.

Detailed orders can be found online.

Search common literature databases:

Common databases of English literature:

Google Schola academic search. Google Academic Search is free. This is what we often use.

WOS: scientific database network. This database is also available at Polytechnic University.

3.Scopus database. I tried this database, but it doesn't work in the University of Technology.

4.4. Use of Springer Link

Use of 5.5. Engineering index

These databases are still very useful for us to retrieve documents, and sometimes they can be used together, so the effect will be better.