The obvious question to ask is how are you promoting your website to generate visitors and what are you selling, are you competitive within your industry, does your website look professional, and is it giving the right kind of information to potential buyers! There are so many factors at play! Sounds like you really need help and advice! I can personally help you quite easily to generate the right kind of traffic without it costing a small fortune but I would need to analyze your website to see if there is anything that would seriously hinder sales when potential customers come through to your site.