match.php

<?php

function matchStringsBetweenWrappers($string) {
    preg_match_all('/\[N\](.*?)\[\/N\]/u', $string, $matches);
    array_walk($matches[0], function(&$item) {
        $item = trim($item);
    });
    return $matches;
}

$string = 'Some text [N]abc_New_New_New[/N] other text [N]ghi_jkl[/N] and other text:;.#{}()[][N]abc_New_[/N].!@';
$matches = matchStringsBetweenWrappers($string);
var_dump($matches);
$string = "في الصيف الماضي ، أنشأ [N]Lego_N [N]Lego_New[/N مجموعة ذات سمة [N]Friends_n.";
$matches = matchStringsBetweenWrappers($string);
var_dump($matches);
$string = "[N]Lego_New[/N] [N]New_Friends_New[/N]  [N]Lego_New[/N] ";
$matches = matchStringsBetweenWrappers($string);
var_dump($matches);
$string = "Some [N]Mercedes-Benz[/N], [N]Chick-fil-A[/N] text [N]abc_New_New_New[/N] other text [N]ghi_jkl[/N] and other text:;.#{}()[][N]abc_New[/N].!@ [N]test-&-Test*!'[/N]";
$matches = matchStringsBetweenWrappers($string);
var_dump($matches);

stdout

array(2) {
  [0]=>
  array(3) {
    [0]=>
    string(22) "[N]abc_New_New_New[/N]"
    [1]=>
    string(14) "[N]ghi_jkl[/N]"
    [2]=>
    string(15) "[N]abc_New_[/N]"
  }
  [1]=>
  array(3) {
    [0]=>
    string(15) "abc_New_New_New"
    [1]=>
    string(7) "ghi_jkl"
    [2]=>
    string(8) "abc_New_"
  }
}
array(2) {
  [0]=>
  array(0) {
  }
  [1]=>
  array(0) {
  }
}
array(2) {
  [0]=>
  array(3) {
    [0]=>
    string(15) "[N]Lego_New[/N]"
    [1]=>
    string(22) "[N]New_Friends_New[/N]"
    [2]=>
    string(15) "[N]Lego_New[/N]"
  }
  [1]=>
  array(3) {
    [0]=>
    string(8) "Lego_New"
    [1]=>
    string(15) "New_Friends_New"
    [2]=>
    string(8) "Lego_New"
  }
}
array(2) {
  [0]=>
  array(6) {
    [0]=>
    string(20) "[N]Mercedes-Benz[/N]"
    [1]=>
    string(18) "[N]Chick-fil-A[/N]"
    [2]=>
    string(22) "[N]abc_New_New_New[/N]"
    [3]=>
    string(14) "[N]ghi_jkl[/N]"
    [4]=>
    string(14) "[N]abc_New[/N]"
    [5]=>
    string(21) "[N]test-&-Test*!'[/N]"
  }
  [1]=>
  array(6) {
    [0]=>
    string(13) "Mercedes-Benz"
    [1]=>
    string(11) "Chick-fil-A"
    [2]=>
    string(15) "abc_New_New_New"
    [3]=>
    string(7) "ghi_jkl"
    [4]=>
    string(7) "abc_New"
    [5]=>
    string(14) "test-&-Test*!'"
  }
}