One of my favorite Japanese words is gambaru, particularly in the imperative, i.e. gambatte. It’s used all the time to encourage people when they’re challenged a lot of a little. From the helpful, engaging site Tofugu, the definition above captures most of the sense of the word, but click on the link above to get the full story.
To really understand the magic of gambatte, you should at least visit Japan or watch a lot of Japanese media. It does uplift and help prevent someone from giving up.