Searching string in php, search field contains whi

This is my code

<div style="display:inline-block; ">    
<?php $a = strtolower($criteria); if (strpos($a, 'fits models from: 11/2000') !== false) { 
     echo 'Fits models from 2000,'; } ?> </div>

I have a problem with the white space. It finds the string if I use only 'fits models from' or if I use '11/2000', but not the two combined. I need them combined or else it's usless.

EDIT: I can't do something like this:

<?php $a = strtolower($criteria); 
if (strpos($a, 'fits models from')  !== false)  
if (strpos($a, '11/2000') !== false) { 
    echo 'Fits models from 2000,'; } ?> </div>

because I want to use it to seperate key factors from a text, which is the car model, from the rest and output that information. If $criteria says 'fits model from 11/2000, but only fits model until 06/2002' then it will output 'fits model from 2000', 'fits model until 2000', 'fits model from 2002', 'fits model until 2002'.

To identity an unknown character:

find the string encoding (probably UTF-8 in your case)
extract a short substring with the character
split it into bytes and display them in hexadecimal
looking at the encoding table, find what character it is with the byte(s) used to encode it

example with the string: "a:\xe2\x80\x85b" that looks like a: b but with a smaller space.

$str = "a:\xe2\x80\x85b"; // I wrote \xe2\x80\x85 only to set $str and to show a working code,
                          // but here I don't know what are the values of these bytes  

preg_match('~:(.*?)b~us', $str, $m); // shortest substring between : and b

echo implode(' ', array_map(function ($b) { return dechex(ord($b)); }, str_split($m[1])));

// e2 80 85

I obtain the 3 bytes e2 80 85, then I search if it represents one or several characters in the unicode table and I find: U+2005 e2 80 85 FOUR-PER-EM SPACE

Conclusion: the unknown character is a FOUR-PER-EM SPACE (unicode point: U+2005) and needs the 3 bytes e2 80 85 to be encoded in UTF-8. So I can write it "\xe2\x80\x85" in a double quoted string.