You (or I) couldn't count the daily tragedy in the world on 1,000 fingers and toes. News has not been in the business of news for decades, at least here in the states. That's why they're registered as entertainment, where they earn by hyping up whatever is hot enough to sell.
Like it or not, people care about that which has a direct impact on them more than that which does not. Be it gas prices, starving children, child soldiers, immigration policy, etc. The world has a vested interest in monitoring Ukraine because it can cause tragedy/disruption an order of magnitude much higher than starvation, at least by countries' vested interests.
Why Yemen? What about South Sudan, Venezuela, Ethiopia, Nigeria, Congo, Iraq, or Afghanistan? What makes one more important than the other?