You need more than a name to register a trademark.
I suggest you read this article to shed a little bit of light on this with real world examples https://newtech.law/en/the-name-of-the-game-video-game-titles-and-trademark-prot...
Generally speaking, names are not protected as such. People and things can have the same name.
But you can protect a brand name. And you can make a game name a brand name - within a given context. And usually you need special things added to the name, so the name becomes an actual logo, complete with graphics. Like "Apple" needs that bitten fruit.
The thing is, these laws are made for a specific purpose, but are often misused. That purpose is to protect a brand. So someone buying a product, would not confuse the competitor brand with your brand. This concept is better understandable for soap and other physical goods.
Also there is the prior usage problem and the scope of the protection, as it is is made for specific markets where you have to register it separatly.
For most indie games this is a non issue. If you are so big that you have to worry about merchandise and trademark branding, you also have you own legal department or at least a publisher that knows this stuff. You just might want to make sure, that the game you develop is not treading on any established brands. Which is very, very hard, if you have a generic or descriptive name.
You immediatly knew that the games you searched and found were not the game you were looking for. So it is evident, that the name alone is not the deciding factor here and a mere trademark would not have helped nor would have been necessary to "protect" the original game from knock-off games, trying to cash in on the similar or even same name.
So i want to know how to avoid this problem in the future(Well assuming my game go viral)
The problem being that someone would search for zombie and not find your game? If you do go viral, it will not matter. Search engines will put relevance on your game by the title words. Even the itch suggestion searchbox will.
Type neigh for example. It already will show you a currently popular game, even though it is an everyday word.