I am new to SQL so please excuse my question if it is simple.

I have a database with a few tables. 1 is a users table, the others are application tables that contain the users preferences for receiving notifications about that application based on the country they are interested in.

What I want to do, is retrieve the e-mail address of all users that have an interest in that country. I am struggling to think about how to do this. I currently have the following query constructed, and the code to populate the values

function check($string)
{
    if (isset($_POST[$string])) {
        $print = implode(', ', $_POST[$string]); //Converts an array into a single string
        $imanageSQLArr = Array();


        if (substr_count($print,'Benelux') > 0) {
            $imanageSQLArr[0] = "checked";

        } else {
            $imanageSQLArr[0] = "off";


        }

        if (substr_count($print, 'France') > 0) {
            $imanageSQLArr[1] = "checked";

        } else {
            $imanageSQLArr[1] = "off";

        }
        if (substr_count($print,  'Germany') > 0) {
            $imanageSQLArr[2] = "checked";
        } else {
            $imanageSQLArr[2] = "off";

        }
        if (substr_count($print,  'Italy') > 0) {
            $imanageSQLArr[3] = "checked";
        } else {
            $imanageSQLArr[3] = "off";

        }
        if (substr_count($print, 'Netherlands') > 0) {
            $imanageSQLArr[4] = "checked";
        } else {
            $imanageSQLArr[4] = "off";

        }
        if (substr_count($print,  'Portugal') > 0) {
            $imanageSQLArr[5] = "checked";

        } else {
            $imanageSQLArr[5] = "off";
        }
        if (substr_count($print,  'Spain') > 0) {
            $imanageSQLArr[6] = "checked";

        } else {
            $imanageSQLArr[6] = "off";
        }
        if (substr_count($print,  'Sweden') > 0) {
            $imanageSQLArr[7] = "checked";

        } else {
            $imanageSQLArr[7] = "off";
        }
        if (substr_count($print,  'Switzerland') > 0) {
            $imanageSQLArr[8] = "checked";

        } else {
            $imanageSQLArr[8] = "off";
        }

        if (substr_count($print, 'UK') > 0) {
            $imanageSQLArr[9] = "checked";

        } else {
            $imanageSQLArr[9] = "off";
        }

and the query

$tocheck = $db->prepare(
    "SELECT users.email
     FROM users,app
     WHERE users.id=app.userid
     AND BENELUX=:BENELUX
     AND FRANCE=:FRANCE
     AND GERMANY=:GERMANY
     AND ITALY=:ITALY
     AND NETHERLANDS=:NETHERLANDS
     AND PORTUGAL=:PORTUGAL
     AND SPAIN=:SPAIN
     AND SWEDEN=:SWEDEN
     AND SWITZERLAND=:SWITZERLAND
     AND UK=:UK");
$tocheck->execute($country);
$row = $tocheck->fetchAll();

This does retrieve data, but only people who's preferences match EXACTLY what is put (so what they haven't selected is taken into account as much as what they have). Any help would be greatly appreciated.