Perhaps you should try some spelling variations:
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang o » nang co, nang ho, nang ro
vi cuu » vinh cuu
vi luu » vi lua
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang o hoi. ((hieu van) or (thien van)) am thuc van hanh ((vi cuu) or (vi luu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang o hoi. ((hieu van) OR (thien van)) am thuc van hanh ((vi cuu) OR (vi luu)) tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang o hoi. ((hieu van) or (thien van)) am thuc van hanh ((vi cuu) or (vi luu)) tre*.