Checkbox Formula - field does not contain text

working with "Contains".
Example: If(Contains(ToText([Approvals Needed:]),"Quality Assurance") and Contains([Approvals Logged],"Quality Assurance"),true)

However, I cannot figure out how to change it to work from the condition that the field "does not contain" something.
Example using "excludes" as the opposite: If(Exludes(ToText([Approvals Needed:]),"Sales"),true)

_I do not know how to write this where not having certain text included in the field is the condition. Any help?

Thank you~