How to search all the fields in address as one string
This isn't a feature that exists out of the box - but addresses support custom fields, so if you're comfortable writing an extension, you could do this.  Create an extension with a hook_civicrm_pre that looks something like this:

function sharedaddresschanges_civicrm_pre( $op, $objectName, $id, &amp;$params ) {
  if (($op == 'create' || $op == 'edit') &amp;&amp; $objectName == 'Address') {
    $result = civicrm_api3('CustomValue', 'create', array(
      'entity_id' =&gt; $id,
      'custom_xx' =&gt; "street_address supplemental_address_1 city etc etc."
    );
  }