Adding books/series

[Damselflies]

So I've been trying to organise my MASSIVE list
and found a couple books that dont have the grey () when they're in a series

Duology (dont know how the author calls this duology)
Book 1: https://www.goodreads.com/book/show/1...
Book 2: https://www.goodreads.com/book/show/1...

Duology pretty monsters, on book page (), but not on want to read shelf
https://www.goodreads.com/book/show/8...
https://www.goodreads.com/book/show/7...

Books/editions from a serie that dont have the () when added to read list but do have it when you go to the book page:
https://www.goodreads.com/book/show/8...
https://www.goodreads.com/book/show/8...
https://www.goodreads.com/book/show/8...

[Abcdarian]

I added the series info to all editions in the Pretty Monsters series.
Not knowing the series name, left your first request.

For your third request, there are way too many editions of those books to go in and add the series info to all of them. Please give a link to the particular edition you want it added to in each case.

[Damselflies]

Hmm I thought it send the correct edition.
Does this help ?:
ISBN 9780316905732 Tunnels of Blood (Mass Market Paperback)
ISBN 9780316016650 The Lake of Souls (Paperback)
ISBN 9780316905725 The Vampire's Assistant (Mass Market Paperback)

And I can try searching the name of the duology, but I'm not sure if the author gave a name to the duology.

[Abcdarian]

Series info added. Sorry, I thought you had just linked to the editions in general.