The girl on this picture is from 3D animation called Takarasagashi no Natsuyasumi (たからさがしのなつやすみ) that was created by Sandwichworks. (さんどいっちわーくす) by the way and here is the offical site of said animation http://www.kap3d.com/wordpress/

Edit: Sorry for my original insufficent post, had to edit it in order to clear misunderstandings.

Qpax said:

This character from this 3D animation by Sandwichworks by the way called Takarasagashi no Natsuyasumi:

http://www.kap3d.com/wordpress/

Are you sure this is the name of the character? Seems much more the name of the animation to me (didn't see the said animation). Taking the simplest meaning, that would mean "Summer Vacations of Treasure Hunting"...

Can't wait for the second part

You can get it her as direct download in 12 pieces
http://www.zeoarchives.net/2014/02/3d-video-summer-vacation-of-search-for.html

or torrent
http://sukebei.nyaa.se/?page=view&tid=385645