<?php
$text = "ác, def ác ghi ác xyz ác, jkl";
$search = "ác";
$_x_word = '/(\s)'.$search.'(\s)/i';
echo count($match_words);
PD9waHAKCiR0ZXh0ID0gIsOhYywgZGVmIMOhYyBnaGkgw6FjIHh5eiDDoWMsIGprbCI7CiRzZWFyY2ggPSAiw6FjIjsKJF94X3dvcmQgPSAnLyhccyknLiRzZWFyY2guJyhccykvaSc7CnByZWdfbWF0Y2goJF94X3dvcmQsICR0ZXh0LCAkbWF0Y2hfd29yZHMpOwplY2hvIGNvdW50KCRtYXRjaF93b3Jkcyk7