search and replace strings with space in php

Should work, can you show the code? What version of PHP?

@REALRANDYALLEN - thanks for replay.

the php version i'm usig is 5.4.12.

this is my code :

    // delete from .conf file
   // for example $survey_queue is 8001
    $res  = $conn->query("SELECT * FROM settings WHERE id = $id");
    $row  = $res->fetch_assoc();
    $survey_queue = $row['survey_queue'];
    $conf  = "[$survey_queue](+)
    setinterfacevar=yes
    ";
    $path_to_file = '../../etc/queues_post_custom.conf';
    $file_contents = file_get_contents($path_to_file);
    $file_contents = str_replace("$conf","",$file_contents);
    file_put_contents($path_to_file,$file_contents);

and this is the queues_post_custom.conf

and its content when i echo the content:

echo $file_contents;
 //is:
[8020](+) setinterfacevar=yes [8021](+) setinterfacevar=yes [8022](+) setinterfacevar=yes [8024](+) setinterfacevar=yes [8001](+) setinterfacevar=yes [8005](+) setinterfacevar=yes 

All I want is to remove for example

[8005](+)
setinterfacevar=yes

// or somthing else like that

thanks.

problem solved , my mistake was in spaces in search word.