You can use patterns and regular expressions (regex) to find and use custom snippets of data from documents.
Regex is a formal syntax for searching through text. It's very powerful, but can be hard to grasp.
You can use patterns can acheive some of the same complexity without attempting to grasp regex.
This rule will find all files that contains an email address from the @gmail.com domain, and move them to a folder.
I've created a pattern with the format [text]@gmail.com.
You can build patterns of the following elements:
Digit: A single digit, 0-9
Number: Any number, of multiple digits
Number with -,.: Also includes numbers like -14.534,56 or 34,349
Character: A single character a-z or A-Z, or any non standard character like æ, ø, å
Word: A word consisting of any number of characters, but not spaces and signs like "," and ".".
Text: Characters, numbers, signs, but not space or or white space
White space: spaces, tabs, line breaks
For this example i've created a regex that finds email addresses that begins with "b". (The regex here is very simplified, and might not match all valid email addresses).