$list = new \Concrete\Core\Page\PageList();
$currentOptions = $c->getCollectionAttributeValue('at_news');
$values = array();
if (is_object($currentOptions)) {
    echo '<div class="options">';
    $first = true;
    foreach ($currentOptions as $v) {
        if ( $first ){
            $first = false;
            echo $v;
            //This makes it retricted to AND, I want OR.
            //$list->filterByAtNews($v); 
            $values[] = $v;
        } else {
            echo ', ' . $v;
            //This makes it retricted to AND, I want OR.
            //$list->filterByAtNews($v);
            $values[] = $v;
        }
    }
    echo '</div>';
}
 
//This works (only one value hardcoded):
$list->filterByAtNews('value1');
 
//This also works:
$oneValue = "value1";
$list->filterByAtNews($oneValue);
 
//This works too but it filters by AND and by order of Value (value1 first, then value2)
$list->filterByAtNews('value1', 'value2');
 
//This doesn't work:
$list->filterByAtNews($values);
 
//Neither does this:
$commaSeparatedOptions = implode(", ", $values);
$list->filterByAtNews($commaSeparatedOptions);
 
//Or this:
$commaSeparatedOptions = "'" . implode("', '", $values) . "'";
$list->filterByAtNews($commaSeparatedOptions);
 
 
$pages = $list->getResults();
 
foreach($pages as $page) { 
    //All pages of value 1 OR value2 OR any other value from multiple attributes taken from current page
}