Only Show Certain Results

Hi, I have successfully retrieved/displayed the data from this structure:

  "DivisionName": "Division 1A",
    "Standings": [
      {
        "Name": "Virginia City",
        "City": "Virginia City",
        "State": "NV",
        "IsMemberSchool": "Yes",
        "League": "1A Northern - West (8 Man)",
        "Wins": 10,
        "Losses": 0,
        "Ties": 0,
        "WinningPercentage": 1.000,
        "PointsFor": 551,
        "PointsAgainst": 74,
        "LeagueWins": 7,
        "LeagueLosses": 0,
        "LeagueTies": 0,
        "LeagueWinningPercentage": 1.000,
        "LeaguePointsFor": 397,
        "LeaguePointsAgainst": 68
      },
      {
        "Name": "Pahranagat Valley",
        "City": "Alamo",
        "State": "NV",
        "IsMemberSchool": "Yes",
        "League": "1A Southern (8 Man)",
        "Wins": 10,
        "Losses": 0,
        "Ties": 0,
        "WinningPercentage": 1.000,
        "PointsFor": 513,
        "PointsAgainst": 64,
        "LeagueWins": 6,
        "LeagueLosses": 0,
        "LeagueTies": 0,
        "LeagueWinningPercentage": 1.000,
        "LeaguePointsFor": 305,
        "LeaguePointsAgainst": 50
      },
      {
        "Name": "Whittell",
        "City": "Zephyr Cove",
        "State": "NV",
        "IsMemberSchool": "Yes",
        "League": "1A Northern - West (8 Man)",
        "Wins": 10,
        "Losses": 1,
        "Ties": 0,
        "WinningPercentage": 0.909,
        "PointsFor": 612,
        "PointsAgainst": 188,
        "LeagueWins": 6,
        "LeagueLosses": 1,
        "LeagueTies": 0,
        "LeagueWinningPercentage": 0.857,
        "LeaguePointsFor": 430,
        "LeaguePointsAgainst": 146
      }

I am now trying to only display results based on the value under ‘League’. For instance, if I only want to display items that are 1A Northern – West (8 Man) in the League field, how could I do this? I have been unsuccessful using the oneofthesewordsmustbein= shortcode. Thank you.

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