If Framaroot is not working for you, you can use Motochopper as well. Now, I know you might be thinking that this is for Motorola devices but the exploit has been reported to work with other devices running on Qualcomm boards (which your device has) as well. You can check out the method for S4 from here though for your device it would be the same but do remember to disable your phone's firewall and antivirus (if any) before doing this.
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