Anilas Children's Magic Paint with Water Books, Dinosaur, Unicorn, Mermaid & Brave Knight - Set of 4

I bought a set of your magic painting books for my grandchildren and then I noticed you did another magic painting book that had aeroplanes on and as my 4 year old grandson is a MASSIVE lover of planes, I very excitedly also purchased this thinking he would absolutely love it, I have now received these books and to say I am disappointed is an understatement. This book has 2 aeroplanes on the cover, so I opened it up expecting to see lots of different aeroplanes for him to paint and guess what……. NOT ONE single plane in the whole book, can you please explain to me why you would put aeroplanes on the cover and then not a single one in the book? Awaiting your reply.