On the literal level, Ada is looking for her father. Charles's search is more psychological. Physically, he's looking for the village [where he killed a Vietnamese child point-blank]. By extension, if he finds the village, he thinks something will happen and he'll be absolved -- find completion. I suppose it's symbolic of what happened to him in Vietnam. Ada is still looking for what he was. . . . One can never find certainty but that won't stop her from trying. The quest beyond finding him physically is to discover where he comes from, where he's been, what happened to him and by extension what happened to her.
— David Bergen
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