Perhaps you should try some spelling variations:
thuc van » thuc vat, thuc dan, thuc va
khoa hoi » khoan hoi, khoa hoc, khoa doi
van hanh » van thanh, ban hanh, van anh
lai cua » dai cua, hai cua, lai chau
vai cua » dai cua, hai cua, bai cua
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hoa hoi » hoa hoc, hoa doi, hoc hoi
ky lang » ky nang, ky dang, ky tang
hieu le » hieu ve, hieu he, hieu ly
le am » le ham, le nam, le a

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky lang ((hoa hoi) OR (khoa hoi)). hieu le am thuc van hanh ((vai cua) or (lai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang ((hoa hoi) OR (khoa hoi)). hieu le am thuc van hanh ((vai cua) OR (lai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang ((hoa hoi) OR (khoa hoi)). hieu le am thuc van hanh ((vai cua) or (lai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang ((hoa hoi) OR (khoa hoi)). hieu le am thuc van hanh ((vai cua) or (lai cua)) triet*.