Perhaps you should try some spelling variations:
nganh khung » nganh khong, nhanh hung
nghien chu » nghien cuu, nghiep cau, nghiep che
khung hoc » chung hoc, nhung hoc, thuong hoc
hoc nganh » hoc nhanh
sach hoc » cach hoc, sach hoi, mach hoc
nhan dan » phan dau, gian dan, nhan tai
tuan hoc » toan hoc, luan hoc, than hoc
chu tuan » chu xuan, thu tuan, chu quang
hoc mai » hoc ma, hoc dai, hoc bai
khoi va » hoi va, choi va, thoi va
tu sach » thu sach, su sach, te sach
khi va » phi va

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 chu tuan hoc nganh khung hoc mai ((khoi va) OR (khi va)) nhan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach hoc tap, nghien chu tuan hoc nganh khung hoc mai ((khoi va) OR (khi va)) nhan dan".
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien chu tuan hoc nganh khung hoc mai ((khoi va) OR (khi va)) nhan dan*.