Hi Yoichi, your sentence certainly makes sense but could be phrased a little more naturally. My personal format would be: Sometimes I suddenly want to have sweet snacks, and other times I want to have oily/greasy/fatty food (deserve implies that you are owed the food, not that you want it). I think that almost all people/everyone has had a similar experience (using "has had" as a participle makes this sound much smoother). I guess that human bodies know which nutrients we are short of and we have that unwittingly. "try" and "unwittingly" are slight oxymorons as one implies an active process and the other is passive. Shortage of nutrients would make sense but reads very scientifically. I hope this helps!

Sometimes I suddenly want to have sweet snacks, and at another times I crave oily food. I think most people have a similar experience. I guess that our bodies know what they need and we unconsciously try to consume that. I'm not sure our bodies ever need sweet snacks or oily food, but yeah, we all get cravings now and again!