Haskell, Aeson - Is there a better way of getting the info I need from USDA database?

I'm a Haskell beginner trying to learn JSON parsing by going through USDA database.

I want to get the value of "ndbno" key from this link https://api.nal.usda.gov/ndb/search/?format=json&q=potato+salad&sort=n&max=25&offset=0&api_key=DEMO_KEY

The JSON file from that link looks like this:

{
    "list": {
        "q": "potato salad",
        "sr": "1",
        "ds": "any",
        "start": 0,
        "end": 25,
        "total": 251,
        "group": "",
        "sort": "n",
        "item": [
            {
                "offset": 0,
                "group": "Branded Food Products Database",
                "name": "AHOLD, DEVILED EGG POTATO SALAD, UPC: 688267141584",
                "ndbno": "45044170",
                "ds": "LI",
                "manu": "Ahold USA, Inc."
            },
            {
                "offset": 1,
                "group": "Branded Food Products Database",
                "name": "AHOLD, REDSKIN POTATO SALAD, UPC: 688267141591",
                "ndbno": "45044169",
                "ds": "LI",
                "manu": "Ahold USA, Inc."
                },
...

"nbdno" key is 4th in "item"

{-# LANGUAGE DeriveGeneric #-}

module Lib
    ( someFunc
    ) where


import           Data.Aeson
import           Data.HashMap.Strict  as HS
import           Data.List            as L
import           Data.Maybe
import           Data.Text
import           Data.Vector          as V
import           GHC.Generics
import           Network.HTTP.Conduit
import           Text.Pretty.Simple


data Food = Name (String, Text)
          | Stuff (String, Int)
    deriving (Eq, Read, Show, Generic)



someFunc :: IO ()
someFunc = putStrLn "Under Consruction!"


apiKey = "https://api.nal.usda.gov/ndb/search/?format=json&q=chana+dal&sort=n&max=25&offset=0&api_key=jJN9dsKFe507qjLVqbecijtrYB4AiojXVIt1EaEZ"


instance FromJSON Food


unString x = case x of
  String x -> x

unObject x = case x of
  Object x -> x

unArray x = case x of
  Array x -> x


getParsed :: IO ()
getParsed = do
  x <- simpleHttp apiKey
  let y = (unObject . snd . L.head . HS.toList . fromJust) (decode x :: Maybe Object)
      z = (unArray . snd . L.last . L.init) (HS.toList y)
      a = V.map (unpack . unString . snd . L.head . L.drop 5 . HS.toList . unObject) z
      b = V.map (\x -> read x :: Int) a
  pPrint b

The way I implemented it is quite messy, but it gets the job done.

It's just that the code looks really bad and almost impossible to read. So I was wondering if there's a better way of doing that.