Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nganh khoa » nganh hoa, nganh khong, doanh khoa
thanh tao » thanh thao, thanh tai, thanh tay
van thanh » ban thanh, van tuan
hoc nganh » hoc nhanh
khoa hoc » hoa hoc
hoi van » hoi va, hoi dan, hai van
mai hoi » mai khoi, dai hoi, lai hoi
hoc mai » hoc ma, hoc dai, hoc bai
tu sach » thu sach, su sach, te sach
doi tai » hoi tai, dai tai, doi tac
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong 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) or (thuoc sach)) doi tai, nghien cuu mon hoc nganh khoa hoc mai hoi van thanh tao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) doi tai, nghien cuu mon hoc nganh khoa hoc mai hoi van thanh tao*.