Buying a domain to target a keyword - Help!

i still had almost same issue and no one answered it yet.

I was asking the guys if there is difference for sero between.

keyword1-keyword2.com

keyword1keyword2.com

keyword1keyword2.domain.com

www.domain.com/keyword1keyword2

I do believe that all of these will have different results for seo. And i still believe that google has advanced algorithm when they are ranking the results.

Being "exact match" and "relevant match"

If someone types keyword1 keyword2 in google then naturally keyword1 keyword2 is much more relevant then. keyword1 random word random word keyword2

same should go for domain.

if some guy is searching for keyword1 keyword2 and the domain name is keyword1 keyword2 - i think google knows that if the whole domain name is devoted to that subject it should be much more relevant then www.domain.com/keyword1keyword2.php

But still no one answered this question yet