IELTS Vocabulary 8.5 Masterclass Series MegaPack: Advanced Vocabulary Masterclass Books 1, 2, & 3 Box Set: Full Self-Study Course for IELTS 8.5 Vocabulary: ... IELTS Program (IELTS Vocabulary Book 4)

I'm sorry but if you are looking for a comprehensive book for IELTS preparation...I would suggest you should buy "Academic Vocabulary & English Collocations in Use Advanced from Cambridge" this book is lacking in depth however, the price is fine.