Unsurprising. I had a few sets like them too, also lost. Real pity.
There's a collection of short stories which were really good, that I lost, that I cannot find to this day. I can only remember 4 of the stories that were in it, but they were so good they stick in my mind to this day.
The 1st was about a boy who goes to see someone about the theory of past lives. He is put under by hypnosis, and awakens the personality of a dead teen London body snatcher, who tricks the doc into letting him go without reverting to the original boy.
The 2nd I remember is about a cop chasing a London murderer who ends up crushed by the reconnecting leaves of Tower Bridge.
The 3rd is about a guy who smuggles people across the Berlin Wall, who carries out that One Last Job with predictable consequences.
The 4th is a scifi about an "Eastpakt" cyborg sent to assassinate the president of the not!NATO at a ball game. (As you can see, these stories are quite dated.)
I can't remember the rest. I really wish I could find this book again. A lot of the concepts in it whooshed over my head at the time I had it.