Joomla if a query is empty uses a different query

Question

I get the variables city and province from autocoplete google map v3

Check if the query with search by city is full, otherwise filter povincie if empty filter by distance.

Is there an alternative to this that forces me to duplicate joins, where for each query?

Example:

<?php
$city = "Milano";
$povince = "MI";

public function getItmes(){

    $province = JRequest::getVar('p','MI');
    $city     = JRequest::getVar('c','Milano');
    $lat      = JRequest::getVar('lat');
    $lng      = JRequest::getVar('lng');

    // check by city
    $db = JFactory::getDbo();
    $query = $db->getQuery(true);
    $query->select('t.*');
    $query->from('#__table_list as t');
    // Join table
        $query->select('j.name');
        $query->join('LEFT', '#__table_join AS j ON t.id = j.id');

        // more join....
    $query->where('t.city="'.$city.'"');
    $db->setQuery($query);
    $results = $db->loadObjectList();

    if($results) { 
        return $results;
    } else { 

    // check by province
        $db = JFactory::getDbo();
        $query = $db->getQuery(true);
        $query->select('*.t');
        $query->from('#__table_list as t');
        // Join table
        $query->select('j.name');
        $query->join('LEFT', '#__table_join AS j ON t.id = j.id');

        // more join....

        $query->where('t.province="'.$province.'"');
        $db->setQuery($query);
        $results = $db->loadObjectList();

        if($results) { 
            return $results;
        } else { 
            // check by distance
            $db = JFactory::getDbo();
            $query = $db->getQuery(true);
            $query->select('*.t, ( 3959 * acos( cos( radians('.$lat.') ) * cos( radians( t.lat ) ) * cos( radians( t.lng ) - radians('.$lng.') ) + sin( radians('.$lat.') ) * sin(radians(t.lat)) ) ) AS distance');
            $query->from('#__table_list as t');
            // Join table
            $query->select('j.name');
            $query->join('LEFT', '#__table_join AS j ON t.id = j.id');

            // more join....

            $query->where('t.province="'.$province.'"');
            $db->setQuery($query);
            $results = $db->loadObjectList();
            if($results) { 
                return $results;
            } else { 
                return "no results";
            }
        }
    }
?>

This method seems repetitive, What do you recommend?