Search engine OSINT is a collection of techniques that use search strings and operators to refine search queries. There are numerous useful operators that can be used to search for specific information about a site, domain, or company. These operators will differ for various search engines, the examples below apply specifically to Google.
AND includes all specified keywords in query (cyber AND war)
OR searches for the presence of one keyword or another (cyber OR war)
" " searches for a specific pattern of words
Site limits searches to a single domain. site:Microsoft.com
Filetype limits searches to a specified file type. site:Microsoft.com filetype:php
You can also exclude specific file types using site:Microsoft.com -filetype:html
Ext is useful to identify which programming languages are used on the site. site:Microsoft.com ext:jsp, ext:cfm, ext:pl
Intext identifies pages with specific terms in the content of the page intext:"term to search for"
Intitle identifies pages with specific titles or content. site:Microsoft.com intitle:"index of" or "parent directory"
Inurl searches for specific terms in a URL inurl:"keyword