title: Elasticsearch (NEST client) - How to search across multiple indices using OIS
body: <p>I need to search across multiple indices using OIS(Object Initializer Syntax).
  I have seen examples of executing search across multiple indices with Fluent DSL, but I still do not know how to execute an equivalent search with OIS.</p>
  
  <p>Here is my OIS search(Only searching against one index) : </p>
  
  <pre><code>        var searchResult =
              await _client.LowLevel.SearchAsync&lt;string&gt;(ApplicationsIndexName, "application", new SearchRequest()
              {
  
                  From = (query.PageSize * query.PageNumber) - query.PageSize,
                  Size = query.PageSize,
                  Query = GetQuery(query), 
                  Aggregations = GetAggregations()
              });
  </code></pre>
  
  <p>Which modifications can be done, so I can search across multiple indices?</p>