Perhaps you should try some spelling variations:
transport subsidies » transport studies
grants public » migrants public, grand public, plants public
trans public » trails public, means public, towns public
trade public » made public, made publick, bare public

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: public ((((trans public) OR (grants public))) OR (trade public)) transport subsidies.
• The words AND, OR and NOT may confuse the search; try adding quotes: "public ((((trans public) OR (grants public))) or (trade public)) transport subsidies".
• Adding a wildcard symbol may retrieve word variants: public ((((trans public) OR (grants public))) or (trade public)) transport subsidies*.