1. Use double quotes for keywords eg: "xxx"
2. Space or vertical line eg: xxx xxx, xxx|xxx (space is equal to and vertical line is equal to or)
3. Book title eg: "xxx" (find books) "Jane Eyre"
4. Minus sign eg: xxx-xxx (different keywords) 2012-movie
5.filetype: eg: filetype:xxx file type file type commonly used pdf, txt, etc. (to retrieve specific file types)
Others I don’t think are used frequently, so I won’t record them.