没有直接查询对作者回复的函数，只有通过对作者历史的查询过滤出对作者的最新回复

let _this = this
let author = 'lemooljiang'
let replies = []
async function getAllSteemReplies(){
  let res = await _this.steem.api.getAccountHistoryAsync(author, -1, 2000)
  res.forEach(item => {
    if(item[1].op[0] == "comment" & item[1].op[1].parent_author == "lemooljiang"){
      replies.push(item)
    }
  })
  console.log(566, replies.reverse())
}

getAllSteemReplies()

//获取回复的信息：item[1].op[1]
0: Array(2)
  0: 132512
  1:
    block: 38344405
    op: Array(2)
      0: "comment"
      1:
      author: "scisan"
      body: "的确！"
      json_metadata: "{"app":"steemit/0.1"}"
      parent_author: "lemooljiang"
      parent_permlink: "q182tz"
      permlink: "q19zu1"
      title: ""

//获取回复的详细--和文章的查找是一样的
this.steem.api.getContent(author, permlink, function(err, result) {
  console.log(567, err, result)
})
  parent_author: "lemooljiang"
  parent_permlink: "q182tz"
  root_author: "lemooljiang"
  root_permlink: "np3fu"
  url: "/steemjiang/@lemooljiang/np3fu#@scisan/q19zu1"  //原贴地址