docs: update docs for operators

docs/source/tutorials/operators.md

@@ -9,6 +9,52 @@ LiquidJS operators are very simple and different. There're 2 types of operators
 
 Thus numerical operators are not supported and you cannot even plus two numbers like this `{% raw %}{{a + b}}{% endraw %}`, instead we need a filter `{% raw %}{{ a | plus: b}}{% endraw %}`. Actually `+` is a valid variable name in LiquidJS.
 
+## Logic Operators
+
+### not
+
+Negates a condition. Returns `true` if the condition is false, and `false` if the condition is true.
+
+Input
+```liquid
+{% if not user.active %}
+  User is inactive
+{% endif %}
+```
+
+### and
+
+Returns `true` if both conditions are true.
+
+Input
+```liquid
+{% if user.age >= 18 and user.verified %}
+  Access granted
+{% endif %}
+```
+
+### or
+
+Returns `true` if at least one condition is true.
+
+Input
+```liquid
+{% if user.isAdmin or user.isModerator %}
+  You have elevated privileges
+{% endif %}
+```
+
+### contains
+
+Checks if a string contains a substring, or if an array contains an element.
+
+Input
+```liquid
+{% if product.title contains "Pack" %}
+  This is a pack
+{% endif %}
+```
+
 ## Precedence
 
 1. Comparison operators, and `contains`. All comparison operators alongside `contains` have the same (highest) precedence.