# Advanced search techniques

You can perform more advanced searches using quotes, wild cards, or boolean operators to return a smaller set of search results

- When you search in the help system, you can identify some words or phrases as an exact string by enclosing them in double quotation marks.

  For example, when you enter `"log file"` in the Search field, you are searching for all occurrences of the string log file. If the double quotation marks are not entered, topics that contain instances of both the word log and the word file are returned.

- You can use wildcards such as asterisk (*) and question mark (?) in your search to expand your search scope.
  - Use asterisk (*) for multiple unknown or variable characters in the search query. For example, if you enter `par*`, topics that contain partly, participate, partial, and other words that begin with par are returned.
    Note: There is one limitation for the search string: when using a search term with an asterisk that it must be preceded by at least three characters, similarly a search term without a wildcard must contain at least three characters.
  - Use a question mark for a single character in the search query. For example, if you enter `par?`, topics that contain part, but not partial or partly are returned.
  Note: When using a search term with an asterisk (*) that it must be preceded by at least three characters
- You can use Boolean operators AND, OR, and NOT to make your query more specific. For example:
  database AND "log file"
    Narrows the search result to topics that contain both the term database and the phrase log file.
  database OR "log file"
    Expands the search result to topics that contain either the term database or the phrase log file.
  database NOT "log file"
    Narrows the search result to topics that contain the term database but not the phrase log file.
  database OR "data base" NOT "log file"
    Searches for topics that contain either the term database or the phrase data base but not the phrase log file.

Parent topic: Searching the help system