When I do not spend any money in social building because I want to wait a few turns for next trade good available. What shall I do? When I go for "Nothing" all my money is gone isn't it. Is there another choise I could go for? Am I wrong?
The progress you make on any social improvement is not reset when you change projects. You can always stick some expensive project like an Economic Exchange in your queue while you wait those wonders and trade goods to be available.