Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
va dinh » van dinh, va kinh, va tinh
va danh » va dan, va hanh, dia danh
tu sach » thu sach, su sach, te sach
hieu va » hieu qua
nang xa » nang x, lang xa, nang ma
hac tuc » thac toc, thai tuc
hai va » hai van, thai va, hoi va

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