How much RAM i can fix in my laptop?

I have Lenovo Flex 2-14 Laptop
(4th Gen Intel Core i5-
4GB RAM-
500GB HDD+8GB SSD-
14 Inches Touch-
Windows 8.1-
2GB Graphics)
I want to upgrade the RAM from 4 to 12.
Can i directly purchase a 8 GB RAM and attach it.
Or it has special combination.
Tell me What i purchase?

We can't answer your question.
You have to open your laptop ram cover… And see how many ram slots you got.

Normally, is 2 ram slots, 2gb + 2gb = 4gb
or
maybe up to 4 ram slots.

btw, 8gb ram is more than enough.