Please, make sure, you write Boolean Operators in capital letters, otherwise the platform wouldn't catch them.

AND - logical operator, which assumes the presence of all selected conditions at once.

OR - logical operator, which assumes the presence of at least one of the conditions.

NOT - logical operator, which is used before a condition that will be excluded from the search.

"..." - quotation marks used to search for exact terms or phrases.

( ) - brackets define the order in which logical operators work. Used to create complex queries. When forming a string, make sure that there is a pair of closing brackets for each part of the query.

For example: JavaScript AND (React OR Redux OR Vue OR Angular) AND (Less OR Sass)

* - the asterisk is used as a replacement character for any number of letters at the end of a word.

For example:

Without space: Java* (Javascript, Javarush etc.)

With space: Java * ( Java Spring, Java 8 etc.)