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function insertTextBeforeSearchTerm() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getActiveSheet();
  var lastRow = sheet.getLastRow();
  var lastColumn = sheet.getLastColumn();
  
  var docsSheet = ss.getSheetByName("Docs");
  
  var docsNamesArray = ss.getRange("docsNamesRange").getValues(); 
  var docsIdArray = ss.getRange("idRange").getValues();
    
  
  var openById = DocumentApp.openById(docsIdArray[0]);
  var body = openById.getBody();
  
  //Use editAsText to obtain a single text element containing
  //Puts all the text as one string
  var text = body.editAsText().getText();
    //Logger.log(text);
  
  //Finds where "history:" is within the long string of the document
  var history = text.indexOf("History:");
  var searchTerm = "History:"; //or hard-code it in 
  Logger.log(searchTerm);
      //Logger.log(history);
  
    //This is what I need to pull from another sheet... their merged history.
    var ancientHistory = "just another test"
  
  //Inserts the text stored in ancienthistory after the searchTerm and makes everything after the search term bold 
  var historyLocation = body.editAsText().insertText(history + searchTerm.length , "\n" + ancientHistory)
  .setBold(history + searchTerm.length, text.length + ancientHistory.length, false);
}