You cannot reduce the spreads alone, you need to tell your broker that it burdens you a lot. In a wise way, never invest your money to a broker who have a very large spreads. It will only cost you a lot of money and gives you nothing but a headache.

Yes, it is possible for them to reduce the spreads but I think the brokers will not agree because it is the only way for them to get profits. They are making their money through spreads.