The OR and | Operators
This operator is used between synonyms or related words.
Example : [ peanut OR groundnut ]
The query in the example returns pages that include either “peanut” or “groundnut” or both terms, but not pages that contain neither “peanut” nor “groundnut.”
Google allows you to use | in the place of OR.
Note: Google's or-operator is an upper-case [OR]. Lower-case 'or' won't work and is simply searching for occurrences of the word “or”.
Unlike OR, a | (vertical bar) need not be surrounded by spaces (e.g. peanut|groundnut )
Note: This functionality is also available through Advanced Search page. Look at the following example: