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

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 process")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"film producers\") or (((\"food producers\") OR (\"food process\"))))".
• Removing quotes may allow a broader search: (( film producers ) or ((( food producers ) OR ( food process )))).
• Adding a wildcard symbol may retrieve word variants: (("film producers") or ((("food producers") OR ("food process"))))*.