new keyword for website

Hello i hope i am posting this in the right place. I am new to the community and have really enjoyed reading the articles posted here. I have a question though i have an affiliate site up and running and then i realized i had messed up on my keyword research did a broad search instead of exact and well traffic is garbage . so recently i went thru and changed my keyword on my site from title to headers and changed my articled to be keyword rich articles for the new keywords. i have been building backlinks with the new keywords as anchor text but big g still is not ranking me for these new keywords they are not even listed in the webmaster tools.

Is there something else i need to do to get big g to recognize the new keywords or am i just sol?

change site domain name