Perhaps you should try some spelling variations:
"film producers" » "film producer", "films produced", "rice producers"
"food producers" » "food products", "food process", "food producing"
"food product" » "food products", "wood products", "food production"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("film producers") OR ((("food producers") OR ("food product")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"film producers\") or (((\"food producers\") OR (\"food product\"))))".
• Removing quotes may allow a broader search: (( film producers ) or ((( food producers ) OR ( food product )))).
• Adding a wildcard symbol may retrieve word variants: (("film producers") or ((("food producers") OR ("food product"))))*.