Some cinematic techniques used in The Pursuit of Happyness (2006) by director Gabriele Muccino have to do with setting, props and motion. Many settings have solid white (or clear) backgrounds with nothing added to the background mise en scene, which illustrates the bleak circumstance and the opportunity to write a new page of Chris Gardner's life. Props consistently encumber Chris. Though he isn't by any means a "prop," Chris is equally encumbered by his young son for whom he must care. This signifies the fettered struggle Chris wrestles with, making it more meaningful than a similar struggle of an unencumbered man. Chris is frequently shown in motion. Though this is the actual representation of a true story, the emphasized motion emphasizes the enormity and urgency of Chris's struggle and efforts.
It is difficult to tell from your question what kind of "techniques" you are evaluating, but looking at the film from a general overview, one thing you could discuss is the character development of Will Smith's character. This film is follows a very standard linear plot-line of the rags-to-riches story, where the protagonist is successful by pulling himself up by his own bootstraps, so to speak. The conflict is obvious, there is a very clear series of complications (which build emotional connection as well as suspense), and these result in a heightened sense of accomplishment at the end when he lands the job despite all circumstances working against him. From beginning to end, Will Smith's character goes through some very clear character changes as he develops a sense of his own priorities. Though he lands a corporate job opportunity, his real character development is in the form of fatherhood: protector and provider.