Everyone has issues that arise for them from time to time. But for the Joads it seemed as though the problems never ended. The two main problems though have been: Prejudice, and ignorance.
The first problem is prejudice, With how the Joads ended up having to move to California in search of jobs to be able to feed their families. The most prejudice came from the police, they weren't understanding in the fact that "Okies" needed the money and needed a place to get a job and stay.
Ma mentions in chapter 22 how the family traveling has changed her by saying that the people who removed them from their farm and the police have done something to them, but describes how at home and at ease she feels when she's at the Hooverville surrounded by other "Okies" because they understand her struggle unlike the landowners or police.
The first solution is that if the police men and the people in California were able to understand the situation they came from and the trouble they were in than maybe they would've been more understanding and less people would've died from stress and malnutrition.
The second problem is ignorance, everyone that wasn't able to understand their position was immediately ignorant to their problems. Which caused them to ultimately not care if others ended up getting hurt in the long run.
The second solution was that the only way to fix ignorance is to teach, and after that the people of California could really understand how selfish they were truly being. It was selfish for the people take away their pay when they barely got paid enough in he first place.
In chapter 19, it's mentioned how the people in California hate the Okies for various reasons, one being that the workers hate them because they think the Okies will "steal their jobs" because they're more desperate and would settle for less pay than an average worker; however, there's always the possibility that they're just taking the jobs that are already open that no one else wants to do, or they aren't educated enough to do jobs that would pay good money anyway. The people hate them because they don't know anything about them other than they're all desperate, but they aren't considering what brought the Okies there in the first place, and they didn't take the jobs that are especially crucial to society like a doctor or teacher. They're farmers. Let them farm.
I feel like if the "Okies" could've went without being prejudiced or everyone around them wasn't so ignorant that the story would've been way different, less people would've died and The Joads would've ended up much happier. Even though that's not how life works.
People these days go through this a lot, many people surround themselves with others that don't care about anyone else's problems but their own. So the struggles that the Joads went through as extreme as they seemed, can ultimately relate to our problems today and that's why.