Perhaps you should try some spelling variations:
thien van » thi van
thue hanh » thue thanh, thuc hanh, thuy hanh
sach thue » sach thu, sach thieu, sach tham
hieu van » hieu va, lieu va, hieu ve
van hanh » van thanh, ban hanh, van anh
duc van » duc va, duc tan, duc manh
lai cua » hai cua, lai chau, thai cua
vu sach » vu bach, su sach, vu khach
cam duc » cam xuc, cao duc, pham duc
hanh va » hang va, hanh vi
va hoi » xa hoi, va hoc, va 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 thue hanh va hoi. ((hieu van) or (thien van)) cam duc van hanh ((lai cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach thue hanh va hoi. ((hieu van) OR (thien van)) cam duc van hanh ((lai cua) OR (dai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: vu sach thue hanh va hoi. ((hieu van) or (thien van)) cam duc van hanh ((lai cua) or (dai cua)) tre*.