.//*[@id='contentText']/table/tbody/tr[2]/td/table/tbody/tr/td[1]/table/tbody/tr[9]/td/table/tbody/tr/td[1]/strong[2]

.//*[@id='contentText']/table/tbody/tr[2]/td/table/tbody/tr/td[1]/table/tbody/tr[10]/td/table/tbody/tr/td[1]/strong[2]

// Get the content or container
WebElement content = driver.findElement(By.id("contentText"));

//Get the table of users
WebElement tblUsers = content.findElement(By.xpath(".//table/tbody/tr[2]/td/table/tbody/tr/td[1]/table"));

// Get the rows which change always as and when users are added
WebElement allUsers = tblUsers.findElements(By.xpath(".//tbody/tr"));

// Loop through each row of users table
for(WebElement user : allUsers) {

   // Get the username
   WebElement username = user.findElement(By.xpath(".//td/table/tbody/tr/td[1]/strong[2]"));
   System.out.println("Username: " + username.getText());
}