Lenovo S820 bootloader problem

Hello everyone.
I am trying to get into the bootloader, so i will be able to use fastboot commands.

So, first i tried to get into the bootloader by pressing the physical keys:
if power button and both volume keys are pressed i get into Android System Recovery(3e).
if power button and volume down key are pressed i get into meta mode.
if power button and volume up key are pressed i get into factory mode, which is entirely in Chinese.
in all 3 occasions, fastboot devices command did not reply anything....

Now the device is recognized by adb (i made the udev rule for it and everything works fine), all commands are working as should except one.
all except one: "adb reboot-bootloader" or "adb reboot bootloader" or "adb reboot fastboot" do not do anything. they just reboot the device into android os.
even "adb reboot recovery" works correctly...

Lenovo S820 is a new device. it was released in 2013, is it possible that it doesn't have proper fastboot mode??? or is it possible that it needs to be unblocked/unlocked in some way???

What should i do? I need some guidance.

P.S.
Android system recovery <3e> options are:
reboot system now
apply update from ADB
apply update from sdcard
apply update from sdcard2
apply update from cache
wipe data/factory reset
wipe cache partition

in Meta mode just get this: Have been in meta mode, long press the power button and the normal boot.

factory mode (which is completely in chinese) has 8 options.
-EDIT-
I am 100% sure that i found the translations of the 8 options of the factory mode:
Manual Test
Auto Test
Item Test
Test Report
Debug Test
Clear eMMC
Version
Reboot