Do an internet search on GERD and there is a lot of information. Try to stay sites such as medline or some research hospital that would have valid information.
The maker of Nexium has good info including what to stay away from. It is at GERD.com
Basically stay away from:
acidy foods such as oranges, tomatoes, vinegar, etc.
chococate, peppermint, coffee (including decaf); carbonated beverages.
Also you should probably raise the head of your bed and not lay down for 2-3 hours after eating.
It may not be reflux. there are a bunch of things that disguise as reflux including candida. Get tested.