Try using a Boolean symbol (& / !) between words to construct more precise queries.

This means that if there is no operator between two terms, the OR operator is used.

Using this operator, each Boolean expression must be true in order for the entire expression to be evaluated as true

A Boolean operation that yields "true" if and only if one of its operands is true and the other is false.

OR - Binary operator that yields TRUE if at least one operand is TRUE.

You can use a more complex queries that use a Boolean operator, such as AND, OR, NOT, and NEAR.

When there is only one event, clicking on the boolean command (1) will create another event linked to the other one according to that operation.

The bitwise OR operator | always evaluates both of its operands, whereas the boolean OR operator || evaluates its right operand only if its left operand is false (zero).

You can use more complex queries that use a Boolean operator, such as AND, OR, NOT, NEAR, or ONEAR.

The Multi-Field Search lets you search more than one word group at the same time, with "AND" between them.

Similarly seems like the authors are not aware that & is also a valid boolean operator, the difference with && being that it does not bypass.

Atom fields are searched only when the query string does not contain any boolean operators (AND, OR, NOT).

Searches with OR and no other Boolean operators produce the same results as selecting the Any Of The Words option.

A first software object may be selected and activated by associating it with a desired Boolean operator, for example, by clicking and dragging the first software object onto the icon for the desired Boolean operation.

The operator AND is known as a Boolean operator, named after George Boole (an English mathematician) who devised a system of algebraic logic in the 19th century known as Boolean Algebra.