Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
tru nang » tri nang, truc nano, thi nang
hanh dai » hanh tai, hanh dao, vanh dai
tra nang » thi nang, kha nang, da nang
hieu va » lieu va, hieu qua
cao tuc » dao tuc, cao duc, cao suc
va hanh » van hanh, va thanh, va danh
tu nang » tu nong, tu nano, tu lang
te sach » toc sach
va cao » va cac, va co, va dao
tuc va » thuc va, truc va, tuc xa
dai va » mai va

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 ((tu nang) or (((tru nang) OR (tra nang)))) xa hoi. hieu va cao tuc va hanh dai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nang) OR (((tru nang) OR (tra nang)))) xa hoi. hieu va cao tuc va hanh dai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((tu nang) or (((tru nang) OR (tra nang)))) xa hoi. hieu va cao tuc va hanh dai va triet".
• Adding a wildcard symbol may retrieve word variants: te sach ((tu nang) or (((tru nang) OR (tra nang)))) xa hoi. hieu va cao tuc va hanh dai va triet*.