Knocking

[Talla]

Hi On my Insignia touring sometimes when i go onto my drive over a small kerb i get a Knock from what seems to be under the front of the Engine bay.

Anti Roll bar area but not present if i drive over a pot hole seems to be when the left wheel hits the kerb any help would be appreciated.

can't see anything obvious under the car although it could be bushes but not sure which ones