Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
danh nhan » doanh nhan, thanh nhan, benh nhan
sach hoi » sach doi, sach moi, cach thoi
hoc toan » hoc tan, hop toan, hoa toan
toan hoa » toan khoa, toan hoat, toan hoc
nhan dan » phan dau, gian dan, nhan tai
su sach » so sach, vu sach
cua tin » cua tinh, chua tinh, cua sinh
tin hoc » sinh hoc
ma hoi » mai hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach hoi dap, nghien cua tin hoc toan hoa hoc ((ma hoi) or (xa hoi)) danh nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoi dap, nghien cua tin hoc toan hoa hoc ((ma hoi) OR (xa hoi)) danh nhan dan.
• Adding a wildcard symbol may retrieve word variants: su sach hoi dap, nghien cua tin hoc toan hoa hoc ((ma hoi) or (xa hoi)) danh nhan dan*.