Perhaps you should try some spelling variations:
cach thoi » cac thoi, cach thuc, cach noi
goc khanh » ngoc khanh, ngoc thanh, quoc khanh
khanh hoa » thanh hoa, hang hoa
thoi dai » hoc dai, hoi dap, hoi dan
cam nhan » ca nhan, cam nang, cu nhan
cam chan » dan chan
su cach » su sach, tu cach, su cac
cuu mot » cua mot, cuu mo, huu mot
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su cach thoi dai, nghien cuu mot goc khanh hoa hoc ma hoi ((cam nhan) or (cam chan)) van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su cach thoi dai, nghien cuu mot goc khanh hoa hoc ma hoi ((cam nhan) OR (cam chan)) van.
• Adding a wildcard symbol may retrieve word variants: su cach thoi dai, nghien cuu mot goc khanh hoa hoc ma hoi ((cam nhan) or (cam chan)) van*.