Website Keywords research

I have a life insurance website, I need an expert seo person to do keywords research to find new topics to talk about, you need to check all the long tail keywords that we have already discussed in our blog (60 articles already displayed). and find new keywords/topics with low to medium search volume. I need you to find me around 500 new keywords that I didn't yet discuss. I won't accept keywords about topics about old articles found in our website. You need to be expert in this kind of jobs. I will pay $30 for such small job.