title: Correct index for partial search in Elastic
body: <p>I have 3 fields, ID, reference_id, and postal_code. I would like to be able to search using these fields, e.g.:</p>
  <p>If ID is ABCDEFGH, searching DEF will show it.
  If there are postal codes 29019 and 27829, searching 2 will show both. Search 29 will show 29019</p>
  <p>Is this autocomplete filter? or wildcard filter? I read in Elastic docs that its bad to put * in front and end of the value of wildcard filter, so I'm wondering what's the best filter to achieve this.</p>
  <p>Thanks</p>