All list responses from queries return paginated results. To simply query the first 10 threads in your workspace, you can use the following query: 
query {
  threads(page: 1, take: 10) {
    entities {
      id
      body
    }
    hasNext
    hasPrevious
    page
    total
  }
}
To query the next 10, simple change the page value to 2. You can do this as long as hasNext is true. 
query {
  threads(page: 2, take: 10) {
    entities {
      id
      body
    }
    hasNext
    hasPrevious
    page
    total
  }
}
The first 20 results are returned by default without query arguments. 
query {
  threads {
    entities {
      id
      body
    }
    hasNext
    hasPrevious
    page
    total
  }
}