diff --git a/docs/tutorials/security-validator-config.rst b/docs/tutorials/security-validator-config.rst
index a9ec70e..aec8d7d 100644
--- a/docs/tutorials/security-validator-config.rst
+++ b/docs/tutorials/security-validator-config.rst
@@ -97,8 +97,9 @@
     **ATTENTION: A packet that satisfies all the filters may not be valid**.
 
 The property **checker** defines the conditions that a matched packet must fulfill to be
-treated as a valid packet. A rule must have at least one **checker** property, a packet is
-treated as invalid if it cannot pass none of the checkers.
+treated as a valid packet. A rule must have at least one **checker** property. A packet is
+treated as valid if it can pass at least one of the checkers and as invalid when it cannot
+pass any checkers.
 
 **filter** and **checker** have their own properties. Next, we will introduce them
 separately.