The previous users were correct mate.
It is bolts that you use. The same as for the rest of the printer.
I dont know where or what manual you are talking about, but understand it is interpreted (poorly) from chinese (where the Anets are made) to english. I generally call this chinglish. I have many manuals and instructions showing the poor level of interpretation fails to back this up.
In regards to solving your problem.
A: listen to people who are trying to help and dont instantly count what they are saying is wrong.
B: A little bit of research goes a long way.
C: Click on this link … https://youtu.be/-tiHfzBQZpI
D: scroll across to the 11:20 mark and it will clearly show you the bolts required and how to assemble it correctly. I would strongly, very very strongly, suggest you watch this and the second video on how to assemble this machine.
E: Watch the videos again!
By watching the videos, you will get a better understanding how to apply the upgrades you are going to print etc and probably eliminate any future build questions you may have.
Im not trying to be harsh or too hard on you. But it bugs me when people are given an answer and the questioner fires straight back saying your wrong!
If you have young children, or have been around them, they are very very smart. They always ask why first.
Good luck and please keep us posted on your progress.