Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
thanh di » thanh doi, thanh de, thanh do
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
duc ban » duc tan, duc van, dua ban
su viet » so viet
tu sac » tu sach, tu cac, tu san
ma hoi » mai hoi, xa hoi, ma 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 sac) or (su sach)) ky nang ma hoi. hieu van pham duc ban thanh di ((cua vat) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (su sach)) ky nang ma hoi. hieu van pham duc ban thanh di ((cua vat) OR (su viet)).
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (su sach)) ky nang ma hoi. hieu van pham duc ban thanh di ((cua vat) or (su viet))*.