How can get specifying columns in relationship

Questions and Answers
1

I have a query to get post:

await strapi.services.post.findOne(ctx.query, [
      "user",
      "user.posts",
    ]);

And this is result:

{
id: 1,
slug: "4-javascript-projects-to-build-fast-and-get-hired-in-1-month-0wj0OdhzT",
title: "4 JavaScript Projects To Build FAST And Get Hired In 1 Month",
user: {
id: 1,
username: "chengcit",
email: "cheng.cit@gmail.com",
posts: [
 {
  id: 1,
  slug: "4-javascript-projects-to-build-fast-and-get-hired-in-1-month-0wj0OdhzT",
  title: "4 JavaScript Projects To Build FAST And Get Hired In 1 Month",
  type_of: "article",
  views: "8"
},
{
  id: 7,
  slug: "huong-dan-agularjs-tieng-viet-fziCQcqnt",
  title: "Hướng dẫn AgularJs Tiếng Việt",
  type_of: null,
  views: "8"
}
]
}
}

But i want only get some field in relationship Post ,particular is:

{
id: 1,
slug: "4-javascript-projects-to-build-fast-and-get-hired-in-1-month-0wj0OdhzT",
title: "4 JavaScript Projects To Build FAST And Get Hired In 1 Month",
user: {
id: 1,
username: "chengcit",
email: "cheng.cit@gmail.com",
posts: [
 {
  slug: "4-javascript-projects-to-build-fast-and-get-hired-in-1-month-0wj0OdhzT",
  title: "4 JavaScript Projects To Build FAST And Get Hired In 1 Month",
},
{
  slug: "huong-dan-agularjs-tieng-viet-fziCQcqnt",
  title: "Hướng dẫn AgularJs Tiếng Việt",
}
]

How can query like this, can everyone help me? Thank you so much!