Search for a keyword using the available keyword tool at Wealthy Affiliate or the Jaaxy. If you have used the two keyword tools when searching for keywords then you will agree with me that you will get awesome keywords.
Do not stuff your headline with unnecessary words that might not give you a good ranking in the search Engines. You have to be specific with your words, that people will use when searching for the information you want to put across in your content.
If you have are writing a procedure to do something say it in your headline with only a few chosen words like 'How to write a killer content that captures the readers attention'.
My keyword here is writing a content, then the other words added are meant to capture the attention of my readers. The content that ranks is what we are looking for, therefore if someone has only 'writing content' and I have mine as a 'Writing a killer content', whose is more specific?
Just as a more specific Niche will rank better, content is what you need to work on to rank best. A long keyword tail will capture the attention of the reader, the need for you to be very specific in your word choice.