Tom is a character in To Kill a Mockingbird who is readily associated with a search for happiness and it this quest that, ironically, puts him in jail, before an angry lynch mob and before an unjust court of law. Tom's search for happiness is for the happiness of the human spirit. Tom sees no racial, social, economic divides; he sees humanity which is worthy of compassion, good will, aid and friendship. For Tom, happiness comes from acting on and extending these virtues. It is in this spirit and in pursuit of his right to happiness that Tom helps out Mayelle, who develops an improper, unasked for and unfounded romantic desire for Tom. When he declines her overtures; when her impropriety shatters his attainment of happiness; when she falsely accuses him before the law, Tom's search for happiness--via respect of human dignity--ironically becomes the open door for his misery. After his arrest, Tom's search for happiness, which will always be founded on the same principles already listed, will have to discover new avenues of fulfillment because, even though bound unjustly by the blind law, Tom will never turn his back on his humanity or the intrinsic humanity of even the most hateful and irrational of individuals,
I think it would be intriguing to focus on the character of Charles Baker Harris, aka Dill, the young friend of Scout and Jem. Dill comes to live next door to the children every summer. Dill is an odd little boy, but Scout and Jem befriend him. He tells them all sorts of wild stories about things he has supposedly done, places he has been. He is obviously trying to make friends with the children.
Dill is an unhappy, abandoned child. He invents stories about his life that are not true. He lives in a city with his mother and stepfather, but they don't pay much attention to him. At one point in the novel, he runs away from his mother, only to be found right there in Maycomb, where he has found happiness.
There are many instances in the novel where it becomes obvious that Dill is a character searching for happiness. Look through the novel for instances that illustrate his special relationship with Scout. He even tells Scout that he will marry her some day and they can live happily ever after in Maycomb.
See the analysis right here on enotes for more ideas.
I think Mayella Ewella and Tom Robinson are both characters who search for happiness. For Mayella, happiness is found through praise or attraction from a male, namely Tom Robinson. Being raised by an abusive father, Bob, Mayella is extremely vulnerable and naive, easily mistaking Tom's neighborly and amiable nature as flirtation.
Tom initally searches for happiness by living according to the golden rule: treating others the way he expects to be treated. He helps Mayella with her dresser, against his better judgement and ignoring the color of her skin and her family's reputation. He is a family man himself, with a wife and young children. When he is on the witness stand it during his trial for allegedly raping Mayella, it is clear he is a man of honor. He is characterized as a man that believes in truth and justice. Atticus would not have taken him on as a client had he not believed in Tom's innocence. Ultimately, Tom's search for happiness through truth and justice fails at the hands of Mayella (as well as others). Mayella lives on after Tom's death/murder knowing the damage she has incurred, further limiting any chances of happiness in her life.