POST /v0/search/subjects 里用 - 排除标签没有效果

如题
`
POST /v0/search/subjects
{
  "keyword": "",
  "filter": {
    "meta_tags": [
      "-科幻"
    ]
  }
}
`
会返回
`
{
    "data": [],
    "total": 0,
    "limit": 10,
    "offset": 0
}
`