Perhaps you should try some spelling variations:
nghien cac » nghiep cach, nghien cuu, nghiep cay
nhanh khoa » nhan khoa, nganh khoa, hang khoa
hoc nhanh » hoc nganh, hoc phan
phan dau » phan tu, hang dau
cau phan » chau phan, cuu phan, cac phan
sach hoi » sach doi, sach moi, cach thoi
khoa hoc » hoa hoc
dong hoc » dong co, dong luc
cac dong » cac duong, cac cong, cac dang
hoi tap » hoi dap, hoc tap, hoi tai
tu sach » thu sach, su sach, te sach
xa hoc » xa hoi, xa hoa, ta hoc
va hoc » van hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach hoi tap, nghien cac dong hoc nhanh khoa hoc ((xa hoc) or (va hoc)) cau phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoi tap, nghien cac dong hoc nhanh khoa hoc ((xa hoc) OR (va hoc)) cau phan dau.
• Adding a wildcard symbol may retrieve word variants: tu sach hoi tap, nghien cac dong hoc nhanh khoa hoc ((xa hoc) or (va hoc)) cau phan dau*.