<?php
$getpositions = [
  'i dont need this NEED1 i dont need this',
  'i dont need this NEED2 i dont need this',
  'i dont need this WANT THIS ALSO i dont need this',
  'i dont need this ANDTHIS i dont need this',
];
$searchpoz = ['NEED2', 'NEED1', 'WANT THIS ALSO','ANDTHIS'];
 
$matches = [];
$getpositions = implode('', $getpositions); // why do we need an array?
foreach($searchpoz as $val){
	$pos = strpos($getpositions, $val);
	if($pos !== false) $matches[$val] = $pos;
}
asort($matches);
print_r(array_keys($matches));

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