Perhaps you should try some spelling variations:
thien van » thi van
thau xay » thuat xay, tu xay, phan xay
nang tai » hang tai, tang tai, sang tai
tai khoi » tai khoa, mai khoi, tao khoi
hieu van » hieu va, lieu va, hieu ve
hanh dai » hanh tai, hanh dao, vanh dai
nam hoc » nam moc, nam hoi, am hoc
va hanh » van hanh, va thanh, va danh
xay ky » tay ky
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: thau xay ky nang tai khoi. ((hieu van) OR (thien van)) nam hoc va hanh dai cua tu~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thau xay ky nang tai khoi. ((hieu van) OR (thien van)) nam hoc va hanh dai cua tu".
• Adding a wildcard symbol may retrieve word variants: thau xay ky nang tai khoi. ((hieu van) OR (thien van)) nam hoc va hanh dai cua tu*.