Users have noted that certain lengthy, complex queries, based on multiple content words take significant amounts of time to process and sometimes can result in timeouts.
Complex queries containing multiple content words or content phrases (without determining precedence or priority) are not specific enough to retrieve optimal query results. Therefore, the query engine is not able to simply process the query quickly, which will sometimes result in a timeout.
When you use two or more operators, the order in which these operators are executed is determined by operator precedence. You can significantly retrieve faster and more relevant queries by overriding the standard order and using parentheses (grouped terms). Content within parenthases is interpreted as one unit. Therefore, the user should always utilize parenthases in complex search statements (more than two operators).
The following operator precedence is applied:
W/n, P/n (these operators are of equal precedence
6.2 Service Pack 1