Here you can find some most popular search examples. Just copy and paste with some modifications into the textarea: 

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The query below finds all issues that are linked as "Blocks", are neither "Closed" nor "Resolved" and which are being linked by issues from the "MORPH" project

{
  "issue.fields.issuelinks": {
    "$elemMatch": {
      "type.name": "Blocks",
      "inwardIssue.key": {"$regex": "MORPH-"},
      "inwardIssue.fields.status.name": {
        "$nin": [
          "Closed",
          "Resolved"
        ]
      }
    }
  }
}

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