The hood should be attached to a fused outlet or a plug in a socket.
Check on top of the kitchen units and in the units around the hood for this.
(I've even see it under the base units, really depends on the kitchen fitters).
Check the fuse in the plug hasn't blown.
Replace the fuse if it has, replace the bulbs and try the appliance again.
Hope this helps
Let me know how it goes or if you need more help