application that roots

Hi guys!
I got a device Q7 android tv box. Few weeks ago I bought sd card, but it is useless at the moment.
I read forums and figured out that the only option, to make the sd card work for real is to root my device.
I tried towelroot, kingoroot, one click root, root master and none of them worked for my device.
Info about my device. It says on the box Q7.
manufacturer: rockchip
model: rk3188
android: 4.4.2
build: rk3188-eng 4.4.2 KOT49H eng.wangjunxu.20141218.102135 test-keys
Is there any possibillity to root this device? Any smart app?
Please help.