CAIXA DE BUSCA QUE FAZ A BUSCA CONFORME VAI DIGITANDO

Ola pessoal alguem poderia me dizer como eu faço para que a minha caixa de busca ela faz a busca no banco conforme eu vou digitado as palavras

este é meu código

<style type="text/css">
{

color: #666;
font: 90%/180% Arial, Helvetica, Sans-serif;
width: 800px;
max-width: 96%;
margin: 0 auto;
}

a {

 color: #69c;
text-decoration: none;
}

a:hover {

 color: #f43319;
}

p {

 margin: 0 0 20px;
}

input {

 outline: none;
}

input[type=search] {

 -webkit-appearance: textfield;
 -webkit-box-sizing: content-box;
 font-family: inherit;
font-size: 100%;
}

input: :-webkit-search-decoration,
input: :-webkit-search-cancel-button {

 display: none;
}

input[type=search] {
background: #1213312

url(https://static.tumblr.com/ftv85bp/MIXmud4tx/search-icon.png) no-repeat 9px center;
 border: solid 0px #000;
 padding: 15px 85px 9px 19px;
 width: 100px;

 -webkit-border-radius: 10em;
 -moz-border-radius: 10em;
 border-radius: 10em;

 -webkit-transition: all .5s;
 -moz-transition: all .5s;
 transition: all .5s;
}

input[type=search]:focus {

 width: 100%;
 background-color: #fff;
 border-color: #66cc75;

 -webkit-box-shadow: 0 0 5px rbga(109,207,246,.5);
 -moz-box-shadow: 0 0 5px rbga(109,207,246,.5);
 box-shadow: 0 0 5px rbga(109,207,246,.5);
}

input:-moz-placeholder {

 color: #999;
}

</style>

<form name="search" method="GET" action="<?php echo $_SERVER['PHP_SELF'] ?>?pesquisar=">
<input type="buscar" name="pesquisar" onclick="on" type="text" autocomplete="off" x-webkit-speech="x-webkit-speech" placeholder="O que deseja pesquisar" required="required" >
</form>