A product is NOT a business … no matter how good that product is. A business has to be built around that product or concept.
So, if you are good at product development, perhaps you need some support on the marketing/sales/commercial side of the venture.
Also, with most investors you are likely to have a better chance of getting funded if you have a co-founder. (Also… entrepreneurship is emotionally draining too, and hence getting a co-founder is a good idea.).
Remember, investors invest in the business case around a concept or product, and the ability of the team to implement that idea in the market. A good product is a good starting point, but neither a necessary condition, and certainly not a sufficient condition for funding. (Why do I say it is not a necessary condition.. because if you have a good product, it is obviously very good. But if you don’t have one, you can easily build one or get one built if you have the right business case that allows you to raise capital to build and market a good product.).