search for multiple keywords with php and mysql (where X like)

To dynamically search all keywords, you can use the explode function to seperate all keywords;

$queried = mysql_real_escape_string($_POST['query']); // always escape

$keys = explode(" ",$queried);

$sql = "SELECT * FROM links WHERE name LIKE '%$queried%' ";

foreach($keys as $k){
    $sql .= " OR name LIKE '%$k%' ";
}

$result = mysql_query($sql);

Note 1: Always escape user input before using it in your query.

Note 2: mysql_* functions are deprecated, use Mysqli or PDO as an alternative

Update 2018 - Note 3: Don't forget to check the length of the $queried variable and set a limit. Otherwise the user can input a vary large string and crash your database.

Don't use mysql_* functions even for testing anymore. They are no easier than mysqli, just in case you think easy to test here then move.

However, you could split your input on a , and try this

<?php

$queried="abc,test, testing";
$values=explode(',',$queried);


$sql="SELECT * FROM links WHERE";
$i=0;

foreach($values as $v)
{
    $v=trim($v);
    if($i==0)
    {
        $sql.=" name LIKE '%$v%'";
    }
    else
    {
        $sql.=" OR name LIKE '%$v%'";
    }

    $i++;
}

$search = mysql_query($sql);
while($searche = mysql_fetch_array($search))
{
    echo "".$searche['link']."</br>".$searche['name']."</br>".$searche['size']."</br>".$searche['category']."<hr></br></br>";

}    
?>

This is a MySQL PDO version of @Hanky Panky's answer

 $queried="abc,test, testing";
 $values=explode(',',$queried);
 $sql="SELECT * FROM citations_new WHERE";
 $i=0;
        foreach($values as $v){
            $v=trim($v);
            if($i==0) {
                $sql.=" name LIKE '%$v%'";
            }
           else {
               $sql.=" OR name LIKE '%$v%'";
           }
           $i++;
         }

$sth = $this->db->prepare($sql);
$sth->execute();
$rows = $sth->setFetchMode(PDO::FETCH_ASSOC);

while($row = $sth->fetch()){
    //enter code here   
}