WebCertain is an SEO company focusing on international markets. One of the main countries that people require help in is Russia, where the major search engine is Yandex. The big difference between Google and Yandex is the way they are structured. Yandex uses a lot of machine learning. The human assessors will say what they want the results to look like, then the algorithm will figure out how to produce the results. Google works the opposite way. However, the Panda update implemented a scalable machine learning technique, so maybe they are headed the same way.
3 Tips for SEO for Yandex
Good content and design
The site must handle the Russian language well
Lots of inbound links, some of which can be paid