How do parentheses AND nested Boolean logic control search execution order in sourcing?

Without parentheses, search engines evaluate operators according to their default internal precedence rules (most search parsers evaluate AND before OR, or read strictly left-to-right). This leads to unintended results. Consider this unparenthesized search query: Java Developer OR Backend Engineer AND Kafka. Because AND takes precedence, the search engine interprets this as Java Developer OR (Backend Engineer AND Kafka). Consequently, the search engine returns any Java Developer in the entire database regardless of whether they know Kafka, plus only Backend Engineers who specifically list Kafka.

By grouping your title synonyms inside parentheses: (“Java Developer” OR “Backend Engineer”) AND Kafka, you instruct the engine to resolve the title group first, and then require that all matching candidates also possess the Kafka skill. Best practice is to organize every query into three or four modular parenthetical blocks joined by AND: [Title Synonyms] AND [Primary Skills] AND [Secondary Skills] AND [Locations].