Nguyen Duy Nam:
Get yourself some Handbooks, they cover a broad range of topics and usually have some very good reference lists for further study and reading. You have to hone in a bit on what you are interested in because Civil Engineering covers a lot of narrower subjects and topics; Structures, Sanitary (Water and Waste Treatment), GeoTech, Highways, Bridges and Transportation, Hydrology, etc. etc. Depending upon your interests, any one of the chapters in one of these Handbooks could make a whole career if studied in more detail, and handbooks like these make great reference books whatever your final direction of study. Some examples....
1. Structural Engineering Handbook, by Gaylord and Gaylord, Pub. by McGraw-Hill
2. Standard Handbook for Civil Engineers, Ed. by Frederick Merritt, Pub. by McGraw-Hill
3. Handbook of Heavy Construction, Ed. by Frank W. Stubbs, Jr., Pub. by McGraw-Hill
Good Luck
