Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
nang ma » tang ma, sang ma, nang cao
hieu va » hieu qua
dat cua » dai cua, day cua, dan cua
mat cua » ma cua, manh cua, mang cua
y nang » ky nang, ly nang, v nang
du va » dau va, tu va, su 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 y nang ma hoa. ((hieu va) OR (lieu va)) cac du va thanh ((dat cua) or (mat cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ma hoa. ((hieu va) OR (lieu va)) cac du va thanh ((dat cua) OR (mat cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ma hoa. ((hieu va) OR (lieu va)) cac du va thanh ((dat cua) or (mat cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ma hoa. ((hieu va) OR (lieu va)) cac du va thanh ((dat cua) or (mat cua)) tre*.