Ransack carries the image of a house being roughly disarranged, as might happen when you are frantically searching for something. This is appropriate given the word's origin. Ransack derives, via Middle English ransaken, from Old Norse rannsaka; the rann in rannsaka means "house." The second half of rannsaka is related to an Old English word, sēcan, meaning "to seek." But our modern use of the word isn't restricted to houses. You can ransack a drawer, a suitcase, or even the contents of a book (for information). A now-obsolete frequentative form of ransack, ransackle, gave us our adjective ramshackle.