chore(docs): Add more info on how to use arbitrary JSON/YAML scan feat

docs/docs/scanner/misconfiguration/index.md

@@ -389,13 +389,24 @@ LOW: Service name "serverless-rest-api-with-pynamodb" is not allowed
 Ensure that Serverless Framework service names start with "aws-"
 ```
 
-You can also pass schemas using the `config-file-schemas` flag. Trivy will use these schemas for file filtering and type checking in Rego checks. If the file does not match any of the passed schemas, it will be ignored.
+!!! note
+    In the case above, the custom check specified has a metadata annotation for the input schema `input: schema["serverless-schema"]`. This allows Trivy to type check the input IaC files provided.
+
+Optionally, you can also pass schemas using the `config-file-schemas` flag. Trivy will use these schemas for file filtering and type checking in Rego checks.
 
 !!! example
 ```bash
 $ trivy config --misconfig-scanners=json,yaml --config-check ./serverless.rego --check-namespaces user --config-file-schemas ./serverless-schema.json ./iac
 ```
 
+If the `--config-file-schemas` flag is specified Trivy ensures that each input IaC config file being scanned is type-checked against the schema. If the input file does not match any of the passed schemas, it will be ignored. 
+
+!!! note
+    If a user specifies the `--config-file-schemas` flag, all input IaC config files are ensured that they pass type-checking. It is not required to pass an input schema in case type checking is not required. This is helpful for scenarios where you simply want to write a Rego check and pass in IaC input for it. Such a use case could include scanning for a new service which Trivy might not support just yet.
+
+!!! tip
+    It is also possible to specify multiple input schemas with `--config-file-schema` flag as it can accept a comma seperated list of file paths or a directory as input. In the case of multiple schemas being specified, all of them will be evaluated against all the input files.
+
 If the schema is specified in the check metadata and is in the directory specified in the `--config-check` argument, it will be automatically loaded as specified [here](./custom/schema.md#custom-checks-with-custom-schemas), and will only be used for type checking in Rego.
 
 ### Passing custom data