Most writers are concerned about voice. When you write, you want to sound like you. Some people come out of the womb with their own voice while others keep writing until they find it. I was definitely in the latter category. When I was a kid, I would copy the voices of authors I loved at the time like Louisa May Alcott. As a teen, I experimented with styles and tried on many writing voices. Sometimes I didn't know if I would ever find me - my own voice and style.
Some stories prove that I wasn't always lost though. One that I wrote as a teenager proves that deep down I did know who I was. I can't remember the title but it centered around a girl whose mother was killed and she actually saw who did it, but that didn't come out until the end and it was sort of about her journey getting there. That story and another one I wrote later always stand out to me as moments when I knew what kind of writer I was. There's lots of confused moments in between, but eventually I came around again.
How did I ultimately find my own voice then? For one thing, I stopped writing what I thought I should write, and focused on what I wanted to write. Switching my focus from literary fiction to mysteries made all the difference. Even though it was terrible, I had the most fun when I wrote the first draft of The Jester's Apprentice. I felt free - and oddly confident considering I didn't know what I was doing! I had found my element and that was half the battle.
Similarly, when writing Dead Locked, I drew from things that I love and make me excited to write - pirates, hidden treasure, blending history with modern times. This combined with characters I loved meant that I pretty much had to write in my own voice because it was all very me. I couldn't force it to happen, but when everything else was right, it came.
If you're still searching for your voice, don't try to force it and don't worry if it doesn't happen over night. Just keep writing and write what interests you, and your own, original voice will follow!