I have tried activating vanilla tabs and search creative tab in config but it doesn't seem to be working. I am playing the current latest version of the mod released on neoforge (1.8.2)

Refer to the tooltips on the bottom left, you should be able to change the page to see them. If you really need the vanilla inventory, disable Legacy Creative Interface in Help & Options > Settings > User Interface > Show Advanced Options

Alright! I will try later. Thank you.

That was literally the first option added that wasn't from LE