How to return document fields in Nodejs (3.0)

I’m using NodeSdk 3.0

async function search(query, limit, skip) {
  try {
    const result = await cluster.searchQuery(
      "test-search",
      couchbase.SearchQuery.queryString(query),
      { fields: ["title"] }
    );

    return result.rows;
  } catch (error) {
    console.error(error);
  }
}

the result not returning the title field.

How to return document fields from searchQuery?