Perhaps you should try some spelling variations:
dong thuoc » dung thuoc, dang thuoc, don thuoc
hoc nhanh » hoc nganh, hoc phan
khong hoc » khung hoc, thong hoc, khong thuoc
sach hoc » cach hoc, sach hoi, mach hoc
cuu cong » cua cong, thu cong, cac cong
cong hoc » dong hoc, cong hoa, cong coc
van nhan » van phan, van thanh, danh nhan
nhan dan » phan dau, gian dan, nhan tai
tu sach » thu sach, su sach, te sach
hai van » thai van, ha van, hai tan
xa hai » xa thai, xua hai, xa hoi

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 hoc tap, nghien cuu cong hoc nhanh ((khong hoc) or (dong thuoc)) xa hai van nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoc tap, nghien cuu cong hoc nhanh ((khong hoc) OR (dong thuoc)) xa hai van nhan dan.
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu cong hoc nhanh ((khong hoc) or (dong thuoc)) xa hai van nhan dan*.