[RiseofAsia]

If still cannot, do you know how to remove your keyboard from laptop?
If dont know, go to youtube to find clip on how to remove laptop keyboard with the similiar laptop model.

Disconnect the keyboard from the ribbon cable that is connected on the motherboard.

Check and clean up the ribbon cable.
Reinsert the ribbon cable into the motherboard connector.

After it is done, switch on your laptop to check the keyboard still functioning properly.
My guess it cable oxidiation.
I will suspect it is cable issue rather than keyboard issue. Good luck!