Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
sach ty » sach y, sach tu, sach thu
va hanh » van hanh, va danh, ban hanh
cao suc » cao su, cao duc
hieu va » lieu va
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
di cua » dai cua, doi cua, de cua

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 ty nang ma hoi. ((hieu va) OR (hieu qua)) cao suc ((va hanh) or (va thanh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ma hoi. ((hieu va) OR (hieu qua)) cao suc ((va hanh) OR (va thanh)) di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ma hoi. ((hieu va) OR (hieu qua)) cao suc ((va hanh) or (va thanh)) di cua tre*".