Where or how can i improve my gameplay with advanced tips?

This question is way too vague... we can impossibly judge what you do and do not know. What areas of expertise would you want to improve, what is hampering your growth as a player?

I admit that it is not simple as a question to ask, I would simply like to improve perhaps in the use of alternative strategies, grow my country's economy more efficiently and make better decisions to win the game.

If you want to improve, play with better players regularly, watch what they do, and ask questions.

When you meet good players in game (not growing like crazy in first few days with gold, then falling apart when they encounter 'good' players in the second week of the game who didn't need to juice their game), ask to join them on the condition they will help you get better and answer questions you have.

Many players will see that you seriously want to get better and respect that...

You've read the forums (much of the help was for CoW 1.0 but much of it applies to 2.0 as well, and much of the theory transferred over without changes)

When you're watching guys play, don't be greedy on the map, be greedy on the game mechanics... pick one subject per game and get that figured out... then move on to the next..

And keep it fun... it's just a game. If it's not serving as a chance to wind down, relax, then you're wasting your time.