There's no native Search/Geocoder in Openlayers 3. But you can use the ol-geocoder extension (I've wrote it) to address this need.
The instructions are at the provided link. I just want to show how I generally use it:
//Instantiate with some options and add the Control
var geocoder = new Geocoder('nominatim', {
provider: 'google',
lang: 'pt-BR',
placeholder: 'Pesquise por um endereço',
limit: 5,
key: '....',
keepOpen: false,
debug: true
});
map.addControl(geocoder);
// I don't want/need Geocoder layer to be visible
geocoder.getLayer().setVisible(false);
//Listen when an address is chosen
geocoder.on('addresschosen', function(evt){
var feature = evt.feature;
var coord = evt.coordinate;
// application specific
app.addMarker(feature, coord);
});