Update Logs Search doc (#15202)

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Co-authored-by: Shannon Anahata <[email protected]>

Author: Dhrumil-Sentry

docs/product/explore/logs/index.mdx

@@ -23,7 +23,7 @@ To get started with Logs, navigate to the [Getting Started](/product/explore/log
 
 ## Viewing and Searching Logs
 
-Raw text search is case sensitive and allows you to search for specific strings within log entries.
+Raw text search is case sensitive and allows you to search for specific strings within the *message* attribute of the Log. Raw text search over the entire log's JSON is not supported.
 
 ![Raw Text Logs Search](./img/LogSearchRawText.png)