Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
cach thuc » anh thuc, cac thu
nang van » dang van, tang van, lang van
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
te sach » toc sach
va cach » va cac
vi su » va su, ki su, oi su
ve su » va su

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) or (te sach)) ky nang van hoa. hieu va cach thuc vat thanh ((vi su) OR (ve su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (te sach)) ky nang van hoa. hieu va cach thuc vat thanh ((vi su) OR (ve su)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (te sach)) ky nang van hoa. hieu va cach thuc vat thanh ((vi su) OR (ve su)) triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (te sach)) ky nang van hoa. hieu va cach thuc vat thanh ((vi su) OR (ve su)) triet*.