您可以传递一个正则表达式， $ c>发生字符串到。例如，键入 Mx 发生 RET DEBUG\ | ERROR 。

I have a plain text file with multiple patterns. Example:

DEBUG: i'm a debug line
DEBUG: Another 1
ERROR: this was an error
DEBUG: Another 2
NORMAL: EMACS
DEBUG: Another 3
ERROR: another error

The idea is to use occur-mode to filter the text file with the patterns i want.
Example: DEBUG and ERROR.

As far as i understood occur only works with single string entry or regex.
How can i use the occur mode to filter more than one string pattern ? If there is another emacs mode to filter strings in text i also accept.

You can pass a regexp that matches either of the strings to occur. E.g., type M-x occur RET DEBUG\|ERROR.