How to custom filter, instead of working with certain fields?

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    "language": "en-US",
    "platform": "MacIntel",
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    "vendor": "Google Inc."
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    "file.encoding": "UTF-8",
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    "java.vendor": "Eclipse Adoptium",
    "java.vendor.url": "https://adoptium.net/",
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    "java.vm.name": "OpenJDK 64-Bit Server VM",
    "java.vm.version": "11.0.14.1+1",
    "os.name": "Linux",
    "os.version": "5.4.0-42-generic",
    "user.language": "en",
    "user.timezone": "Asia/Shanghai"
  },
  "metabase-info": {
    "databases": [
      "mysql",
      "h2"
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    "hosting-env": "unknown",
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        "version": "8.0.23-0ubuntu0.20.04.1"
      },
      "jdbc-driver": {
        "name": "MariaDB Connector/J",
        "version": "2.7.5"
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    "run-mode": "prod",
    "version": {
      "date": "2022-04-07",
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      "hash": "7c3ce2d"
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    "settings": {
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}

Hi @lmm
I don't understand what you are asking for. Try looking in the documentation: https://www.metabase.com/docs/latest/users-guide/expressions.html