What I see here is that the reason you failed in your project is that, the investor doesn't find any profit to your projects. If your project can be profitable then you will not be having a hard time finding investors.
yes that was the cause of failing in my first project, i got past that and got an investor via an event a hackathon. but that didn't go as well, that's when i learned that the team you work with is an essential component as well. I moved on. but the last project I am working on is a local business in my home city, not much investors around to convince, nor much events to help me out in this matter. having trouble finding investors than them not willing to invest. when it comes to profit it is really not that profitable at first. only self sustained but made to grow in future.
I would like Op to understand that getting people to believe in you is like getting them to buy your product which is purely marketing.
Thus, what is your marketing or media strategy. Before marketing comes also, you must have a good product so that when people finally get convinced, the product you have won't be a failure.
If your product is online, maybe you can put a link out maybe you can get better advise.