I have followed the docs and none of these worked:
?$filter=FieldValues/Product_Name eq 'XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX' and ?$filter=contains(FieldValues/Product_Name,'XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX')
However when I searched using
?$filter=Name eq 'Item Name' then it generated a result.
Is there anything that I've missed here? Perhaps a configuration? I have done rebuilding my search index and populated my schema but still to no avail.
EDIT: I'm using Sitecore 9.0.2