Does refusing strenuous, low-paying work—when no other work is available—contradict the principle of taking measures to seek sustenance?

A person's endeavor to earn a living for himself and for those whose maintenance is his responsibility is an act of worship by which he draws closer to Allah. No matter how difficult the work, seeking reward from Allah eases its burden. One should continue in their current job while searching for a better one, and maintain a good opinion of Allah in finding other job opportunities. It is better for a person to work and strive to be self-sufficient rather than asking people, even if his work is difficult, because asking people while being able to earn may be unlawful, and it involves humiliation for the asker and difficulty for the one being asked.