title: Rails searchkick query for multi fields don't work
body: <p>I want to do a searchbar to search a term in many fields of my model.
  For now I have this code :</p>
  
  <pre><code>@query_search = "#{params[:search]}"
  products = Campaign.search query: {match: {name: @query_search}}, fields: [{owner:  @query_search}], misspellings: {distance: 2}
  </code></pre>
  
  <p>the result works only on the <code>name</code> fields (and only on the exact case). the <code>fields: [{owner:  @query_search}]</code> change nothing.
  I tried to do things like this :</p>
  
  <pre><code>products = Campaign.search query: {match: {name: @query_search, brief: @query_search}}, fields: [{owner:  @query_search}], misspellings: {distance: 2}
  </code></pre>
  
  <p>but no result, misspellings don't work either in any case.</p>
  
  <p>So, Anybody has an idea? 
  Thanks !</p>