I think it is very difficult to get merit, I've tried to post according to topic and try to answer as well as possible but until now I have not get merit, maybe I should keep learning to make a good post so I can get merit to raise my account level
No, it is not. Go over your posts and pick one that deserves merit and if it does, I'll merit you. Stop forcing yourself to write for merit, posts like those usually turn out to be forced and confusing.
Try to write posts as you would tell them to your friend, don't write them as you're presenting them to some business corporations (depends from the post) and you'll see merit coming in.
Good opinion to get merit. My several posts are already published. Hopefully, it will be under the radar of senior merit guys for leveraging their merits in my posting.