a single string, to find all files in which the string occurs
two strings separated by '&', to find all files in which both strings occur (overlaps allowed)
two strings separated by '|', to find all files in which one or other (or both) of the strings occur.
After entering a string or strings, either press the Enter key on your keyboard or the "Submit Query" button on the screen. The case of the characters you enter is ignored; otherwise, only exact matches are found. Do not precede or follow a '&' or '|' by a space, unless it is part of the string for which you are searching.