<?php
    $str1 = "OneTwoThreeFourFiveSixSeven";
    $str2 = "OneThreeFourSevenFiveSix";
    if(strrpos($str1, "Two") ){
        echo 'Two is in $str1\n';
    }else{
        echo 'Two is not in $str1\n';
    }

    if(strrpos($str2, "Two") ){
        echo 'Two is in $str2\n';
    }else{
        echo 'Two is not in $str2\n';
    }
?>

Two is in $str1\nTwo is not in $str2\n