I have good knowledge on the wordpress and joomla so can i earn money by these design nor need also more need to know other on the html, php, java. please suggest me.
Mousomihoq,
It would depend on what you are trying to make money doing. Are you talking passive income via advertising or building websites for people? I think you can make money with either of those things just fine without knowing a lot of programming. I have seen people build websites for others who knew very little programming but were very skilled at arranging plugins. The only issues may run into is if a client wants something that there is no plugin for.
This post suggests that building on a CMS can actually be better for clients,
Hope that helps,
Shawn