I didn't know for sure whether it was the same book, but the title 'The World Of The Unknown: Ghosts' was reminiscent of a publication that was in my school library. I can vividly recall seeing 'GHOSTS' in huge font on my first visit to the school and recall taking the book home with me many times over the four year stay at the school.
Back to 2020 - the book was available for £4.08 on the website (it may have changed by the time you're reading this). Prime members were able to get it on the same day, so I chose to have it arrive at my home in the evening.
And here it is:
I am pretty sure this is the same book that was in the school library. The reason why I believe this to be the case is because, in the inside pages, it reads that the edition I had in my hands was published in 2019. However, there are copyrights from 1977 and 2019 on the page.
One thing I absolutely recall from my loaning of the book was a page - or two - of black and white photos of ghosts that were caught on film. I leafed through, and voila:
I'm going to have a proper look through this later on today to see if more memories of mine are jogged.