To see an encyclopedia in a dream refers to decisions and works in life.
To see that you open the encyclopedia and read it in your dream implies that you will speed up in your responsibilities which you have to deliver and you will deliver your work successfully.
To see of buying an encyclopedia in your dream signifies that you will make decisions related to your job or school and these decisions will influence your life positively.
To see of selling an encyclopedia in your dream symbolizes a person, job or place that you will abandon. If you sell the encyclopedia to the person whom you know in your dream, it denotes that your life will change with your decisions about your relationship and the beauties will be with you.
To see a thick encyclopedia in your dream signifies that you will make good works with people whom you will meet during an organization.