elseif search query not working

I have a search form that has 3 elements keywords, Industry ( Dropdown ) & location

I am trying to create search function that will query the DB if all 3 elements are selected or based on individual values OR a combination of any elements having $_POST data submitted

Its just not working

My code for the queries is below

        if(isset($_POST['keywords']))
    {
    $keywords = $_POST['keywords'];
    $viewq = mysqli_query($con,"SELECT * FROM `listings` WHERE (`title` LIKE '%$keywords%' OR `description` LIKE '%$keywords%') LIMIT 0,50");
    $resultsfor = $_POST['keywords'];
    }
    elseif(isset($_POST['keywords']) && isset($_POST['location']))
    {
    $keywords = $_POST['keywords'];
    $location = $_POST['location'];
    $viewq = mysqli_query($con,"SELECT * FROM `listings` WHERE (`title` LIKE '%$keywords%' OR `description` LIKE '%$keywords%') AND (`location` LIKE '%$location%') LIMIT 0,50");
    $resultsfor = $keywords .' jobs in '.$location;
    }
    elseif(isset($_POST['keywords']) && isset($_POST['location']) && !empty($_POST['industry']))
    {
    $keywords = $_POST['keywords'];
    $location = $_POST['location'];
    $catno = $_POST['industry'];
    $viewq = mysqli_query($con,"SELECT * FROM `listings` WHERE (`title` LIKE '%$keywords%' OR `description` LIKE '%$keywords%') AND (`location` LIKE '%$location%') AND (`catno` = '$catno') LIMIT 0,50");
    $resultsfor = $keywords .' jobs in '.$location;
    }
    elseif(isset($_POST['industry']) && empty($_POST['location']))
    {
    $industry = $_POST['industry'];
    $viewq = mysqli_query($con,"SELECT * FROM `listings` WHERE `catno` = '$industry' LIMIT 0,50");
    $resultsfor = $_POST['industry']. ' jobs';
    }
    elseif(isset($_POST['industry'])&& isset($_POST['location']))
    {
    $industry = $_POST['industry'];
    $location = $_POST['location'];
    $viewq = mysqli_query($con,"SELECT * FROM `listings` WHERE (`catno` = '$industry') AND (`location` LIKE '%$location%') LIMIT 0,50");
    $resultsfor = $_POST['industry']. ' jobs in '.$location;
    }
    elseif(isset($_POST['location']))
    {
    $location = $_POST['location'];
    $viewq = mysqli_query($con,"SELECT * FROM `listings` WHERE (`location` LIKE '%$location%') LIMIT 0,50");
    $resultsfor = $_POST['location']. ' jobs';
    }

    $view = mysqli_fetch_assoc($viewq);

Would really appreciate some help, Ive spent loads of time on this Thanks in advance

** It does pull data although not correct, If i search for warehouse ( leave industry dropdown blank ) but set location to Leicester it still queries ALL results not Leicester If I select an Industry from the dropdown menu and leave other fields blank, I get all jobs in all categories not just the category selected

Getting myself confused now