That's a complex question. You'll always find that people who know the company or brand name convert at a much higher rate, since they are looking directly for you.
The two main areas to look at are:
- Are they the right keywords? The wrong keywords will provide the wrong audience, who you will never be able to convert
- Does your landing page provide what visitors want? If you're confident the keywords are relevant, then you should look towards conversion optimisation - changing your site to encourage more sales.
In many industries, you'll be looking at something between a 1% and 5% conversion rate, though, so 10 clicks a day would take several days on average tp provide a conversion, even with everything else being OK!