Understanding how advanced filters work
The default behavior of the advanced filters is to include data based on the filter parameters. To exclude a particular type/group of email conversations, use the negative operators. E.g. To exclude Conversations where the subject line contains a particular keyword or phrase, set the advanced filter to: “Subject – does not equal / contain/begin with – keyword/phrase”
This will filter all data in your account to display only those Conversations where the subject line does not contain the keyword or phrase you want to avoid.