Raft now available on Steam. Raft on Steam
Is this mainly focuses on survival strategies? or this game needs a critical thinking?
I don't think I'd say this game relies all too much on critical thinking. You honestly have an infinite supply of crafting materials as there are debris constantly floating by your raft, available for you to pick up. More than anything I'd say it's about patience. One could say some degree of critical thinking is involved as you want to be prepared to be able to anchor by an island to gather rare resources, as opposed to just floating by.
But otherwise, like I said, it's more about having the patience to gather the resources as they float by. Once you have the basics established, like building a water purifier, cooking station, and a fishing pole, the biggest survival strategy you need to keep in mind is to just have wood and food reserves for when your energy gets low.