Well tell you what you should really read about the numbers before coding it out. Bruteforcing isn't a good practice. You should carefully observe the stuff.
I will give you a simple hint with which you can improve your code.
Lets examine the Fibo series :-
1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, .....
Do you observe something ?
What we observe is that every third number is even.
Well that's your hint for now.