Describe search filters (#7744)

* Describe search filters

* Update servicepulse/all-messages.md

* Update servicepulse/all-messages.md

* Update servicepulse/all-messages.md

* Update servicepulse/all-messages.md

Author: afprtclr

servicepulse/all-messages.md

@@ -51,10 +51,20 @@ The results can be filtered by one or more of the following criteria:
 
 - **Date Range:** Specify the date range along with the time within that range.
 - **Endpoint:** Select a specific endpoint.
-- **Custom Filter:** Perform a free-text search across message data. This also supports wildcards.
+- **Custom Filter:** Perform a free-text search across message data.
 
 By default, the view displays 100 messages but can be customized to display up to a maximum of 500 messages. To display specific messages, modify the filters to narrow down the displayed results.
 
+## Filtering Options
+
+The search filter works in the following way:
+
+- The filter is case insensitive (i.e., `term` and `TERM` will return the same results).
+- A message will be returned if it matches at least one of the terms (i.e., the logical operator between the terms is `OR`).
+- A `*` wildcard can be used to replace a prefix and/or a postfix of a searched term (i.e., `word` will be found by `*rd`, `wo*`, and `*or*`).
+- Other logical operators (e.g., conjunction, negation) are not supported.
+
+
 > [!NOTE]
 > A message's body is searchable only if the body size is under 85kB, within the [`ServiceControl.Audit/MaxBodySizeToStore` size limit](/servicecontrol/audit-instances/configuration.md#performance-tuning-servicecontrol-auditmaxbodysizetostore), and is a non-binary content type.