Perhaps you should try some spelling variations:
khong thuoc » khang thuoc, hong phuoc, khoa thuoc
dong thuoc » dung thuoc, dang thuoc, don thuoc
hoc nhanh » hoc nganh, hoc phan
sach hoc » cach hoc, sach hoi, mach hoc
cuu dong » cuu cong, cuu tong, cuu long
dong hoc » dong co, dong luc
phap vat » phap luat, phap phat, phap viet
tu sach » thu sach, su sach, te sach
va phap » va phat, ban phap
va hoi » xa hoi, va hoc, va hoa

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 dong hoc nhanh ((khong thuoc) OR (dong thuoc)) va hoi va phap vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach hoc tap, nghien cuu dong hoc nhanh ((khong thuoc) OR (dong thuoc)) va hoi va phap vat".
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu dong hoc nhanh ((khong thuoc) OR (dong thuoc)) va hoi va phap vat*.