My name is not updated yet in the owner list. 

Guys, is it u all really satisfied with this nexus 4??? Previously I'm selling my note 2 just same like my note 1. Thanks for advice guys.

What do you mean become common phone????

Can choose the place to backup ?

For your information, nexus 4 never have sdcard..
so missing seems a bit weird

I suggest you flash back the stock rom
Use the nexus toolkit to do it

Look in TWRP pages, see if there's an option to "mount /sdcard"

Did you select external storage during backup? It should be the default one, internal storage.

Just reinstall your TWRP recovery and try again

You want better assurance do it from terminal:

Downlaod the latest img file from http://techerrata.com/browse/twrp2/mako

Switch off your phone.  Boot to fastboot mode .  Plug the phone into your computer.  If you have the right drivers installed, your screen should now say FASTBOOT USB.  Run the following command via the command line:

fastboot flash recovery recoveryfilename.img

Note that you will need to change the last part to match the name of the file that you just downloaded

I dont really understand your question
You must choose recovery to boot to recovery mode by pressing the vol buttons at fastboot mode

when u in fastboot mode. type fastboot devices

should come out like

fastboot
XXXXXXXX

after that proceed what uncle benny tells you.
dam i just realize i dont have adb+fastboot setup in my laptop. this is bad.

Nope, Command prompt,
purely command.

follow the step step by guide I gave just now, you should be fine.
if you have problems with the steps in efrant's guide

go into irc here
http://client02.chat.mibbit.com/?channel=%...r=irc.efnet.org

i have a dinner i have to attend later, but i'll help you out while i still can