Added multisearch usage in documentation (#1863)

Co-authored-by: Fernando Briano <[email protected]>

Author: anandtripathi5

docs/examples.asciidoc

@@ -10,6 +10,7 @@ the Ruby client.
 * <<ex-delete>>
 * <<ex-bulk>>
 * <<ex-search>>
+* <<ex-multisearch>>
 * <<ex-scroll>>
 * <<ex-reindex>>
 
@@ -177,6 +178,20 @@ response['hits']['hits'].count # => 15
 ```
 
 
+[discrete]
+[[ex-multisearch]]
+=== Multi search 
+The following example shows how to perform a multisearch API call on `books` index:
+```ruby
+body = [
+  {},
+  {query: {range: {page_count: {gte: 100}}}},
+  {},
+  {query: {range: {page_count: {lte: 100}}}}
+]
+client.msearch(index:'books', body: body)
+```
+
 [discrete]
 [[ex-scroll]]
 === Scrolling