This is stock rom / firmware is for Lenovo A706. You need to put the file in the SDCARD.
The firmware is not flashable via flashtool. So you cannot use SP Flash Tool. The firmware is in two part. You need to use HJSplit to join the file and to make it usable. If you did not join the file you cannot use the file.
Download the Firmware
Part 1 -- > Part1
Part 2 -- > Part2
You need to create a sdfuse folder in your memory card. It must be in the root example f:\sdfuse or e:\sdfuse like that when you are extracting the file.
Open the firmware file that you have downloaded and put it in the sdfuse folder that you created in your sdcard.
Flashing the firmware (Official guide from Lenovo)
1. Insert the SD card to your phone, insert the battery, then press and hold vol up key and power key till you see the engineering mode on the screen.
2. Press vol down key till cursor on ‘4. SD update’, then press power key to confirm.
3. Check if the version displayed on screen is correct, if yes, then press power key to START. Now the SD update is going.
4. When SD update completes, press power key to REBOOT device.
5. If your device powers up normally and goes to Android setup screen, it is ready to go.
6. If your device can not power up and screen keeps black for a long time(more than 3 minutes), then pull out and re-insert the battery, press and hold vol up&down key and power key till you see the ‘Android system recovery’ displayed on screen with following options: reboot system now; apply update from external storage, apply update from internal storage; etc.
7. Press vol down key till cursor on ‘wipe data/factory reset’, press power key to select.
8. Press vol down key till cursor on ‘Yes –- delete all user data’, press power key to select
9. Wait a while, and device will reboot automatically.
I hope this firmware solve your problem.