multitrack recording drums help!!

Hi i recently bought a recording set for my drumkit. I also bought a mixer/interface the Peavey Pv10 usb i hooked my mixer up to my laptop with cubase 5. When i go yo my device setup it shows a ASIO driver. If i go to VST- connections inputs i want to select 7 busses but if i want to select the channel per bus so for example bus 1 channel 1 bus 2 channel 2 till bus 7 it only shows 2 channels… (stereo) does someone knows how to get more channels?

Sorry for my bad english.