[SOLVED] Asus K555LA Upgrade Ram

Hi all,
I want to upgrade laptop K555LA with more 4gb ram, it's run in chip i5 4210U and i see that type ram DDR3 is compatible with this, so i bought a Kingston ram 4gb DDR3 1600 mhz 1.5V to upgrade it, but the system only detect the Kingston ram in slot that i installed ( the initial ram is not).
So how can i solve this problem?
Can i use another ram with type DDR3L 1600 mhz 1.35V to upgrade the laptop?
Thank all you a lot !