Perhaps you should try some spelling variations:
lang mai » lang dai, lang hai, lang man
van hanh » van thanh, ban hanh, van anh
ve triet » va trien, su triet
tu sach » thu sach, su sach, te sach
sach vu » sach va, sach tu, sach uu
vu lang » va lang, vu dang, cu lang
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » hieu qua
cam luc » cam xuc, cau luc
luc van » luoc van, luu van, duc van
hanh ki » hanh vi, hanh ky, hanh kien
ki ve » ke ve, gi ve, vi ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach vu lang mai hoi. ((hieu va) or (lieu va)) cam luc van hanh ki ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach vu lang mai hoi. ((hieu va) OR (lieu va)) cam luc van hanh ki ve triet.
• Adding a wildcard symbol may retrieve word variants: tu sach vu lang mai hoi. ((hieu va) or (lieu va)) cam luc van hanh ki ve triet*.