|+||Used to include common words|
|“||The words of a query enclosed in double quotes are searched in documents in exactly the order and in the forms in which they occurred in the query. Thus, double quotes can also be used simply to search for a word in a given form (by default, words are found in all forms).|
|NOT||The NOT operator allows you to form a query that is answered by documents that satisfy the left side of the query and do not satisfy the right. For example, a search for dog NOT cat will return all documents that contain the word “dog” and not the word “cat”. This is especially useful in cases where the desired word form is at the same time a form of another word: Zhenya is a proper name, as well as a gerund. If we are looking for a person named Zhenya, you can write Zhenya NOT marry in the query.|
|&&||Two queries connected with the && operator form a complex query, which is satisfied only by documents that simultaneously satisfy both of these queries. In other words, the query dog && cat will only find documents that contain both the word “dog” and the word “cat”.|
|||||A complex query consisting of two queries joined by the || operator is satisfied by all documents that satisfy at least one of the two queries. On request dog || cat there are documents that contain at least one of two words – the word “dog” or the word “cat” (or both of these words together).|
|()||Using parentheses allows you to build nested queries and pass them to operators as arguments, as well as override default operator precedence.|
Organization of a special search. With the help of special search tools, you can search for documents: containing the required data in various fields (title, keywords, description); located on any site; containing certain links, etc. Let’s take a closer look at some of the special search features.
Many search engines allow Web documents to be searched for by text contained in headings. Searching by headings significantly reduces the number of found links, but very accurately displays the desired materials. After all, each Web page can have a title if its author is not too lazy to create it. And the title of a Web page usually accurately characterizes the topic of the material that is contained on it.
For example, if you are looking for information about distance learning, then it is wise to look for pages that have this combination in the title. Thus, unlike a simple query, we cut off those documents where these words are not significant, i.e. do not define the topic of the article.
The operator or command for such a search is title. This operator can be denoted in one of the following ways: title:, t:, title =, $title, and so on. After the operator, I follow the keywords. Some search engines require keywords to be enclosed in parentheses, others are written without parentheses. For example, in Yandex, the search command in the title is written as follows: $title (full-time training).
Site search. With the help of search engines, you can search for information not in the entire Web space, but on a specific site (unless, of course, the latter is indexed by a search engine). The corresponding operator can be denoted in one of the following ways: url=, url:, u:, #url=”. This is followed by the address of the Web site; some systems require the address to be enclosed in quotation marks.
If the query simply writes this operator with the address of a Web site, then a list of documents indexed by the search engine on this site will be obtained. But this operator can be combined with others, thereby searching for information according to all the rules for constructing queries on this site.
In addition, search engines may offer other special search options: search by reference text, search in the document description, search in the keyword list of Web pages, search in figure captions, and so on. You should be aware that the syntax of search queries, and the composition of the available operators, differs in different search indexes. Therefore, before performing a search in a particular search engine, you should study the help page for searching in this system.