Ruby on Rails searching with two strings

I have a model projects. And I have a search form with many search bars. What I want is (within the oder searches) a search bar where you can type in two strings. If you want to find all projects regarding "Graphics Card" and "China" you should be able to type in something like graph chin and all these records will be displayed.

In the Projct model I have this

def self.google(var1, var2)
    where("brief_title LIKE ? and country LIKE ?", "%#{var1}%", "%#{var2}%")
end

In the ProjectsController I have a bunch of code and tryed the following but it doesn't work (look for google)

bunch of other code

else
   @projects = Project.select_stuff(params[:stuff_id]).select_x(params[:x_id]).search(params[:search]).google(params[:var1], params[:var2]).paginate(:per_page => 25, :page => params[:page])
end

Has someone a clue?

Thank you in advance