Perhaps you should try some spelling variations:
hat chau » ha chau, lai chau, hat nhan
vat danh » va danh, van danh, luat danh
cam thuc » am thuc, nam thuc, cam thu
hieu van » hieu va, thien van, lieu va
vu khach » vu khanh, vu khac, vay khach
nang ma » tang ma, sang ma, nang cao
van cam » van nam, van lam, van cau
ly nang » ky nang, ly hang, ly vang
hoi cau » hoi chu, hoc cau, hoa cau
vu sach » vu bach, su sach
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: ((vu sach) OR (vu khach)) ly nang ma hoi. hieu van cam thuc vat danh ((hoi cau) or (hat chau)) treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (vu khach)) ly nang ma hoi. hieu van cam thuc vat danh ((hoi cau) OR (hat chau)) treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) OR (vu khach)) ly nang ma hoi. hieu van cam thuc vat danh ((hoi cau) or (hat chau)) treo".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) OR (vu khach)) ly nang ma hoi. hieu van cam thuc vat danh ((hoi cau) or (hat chau)) treo*.