Perhaps you should try some spelling variations:
va thanh » ban thanh, va tinh, le thanh
te sach » toc sach
nang ma » tang ma, sang ma, mang may
hieu va » lieu va, hieu qua
hai cuu » hai cua, hai chu, hai cuc
cuu tre » cua tre, cau tren, cau treo
va cam » va cham, va cac, va cao
cam tu » cam thu, nam tu, dam tu

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) OR (nang cao)) hoi. hieu va cam tu ((va thanh) or (gia thanh)) hai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((nang ma) OR (nang cao)) hoi. hieu va cam tu ((va thanh) OR (gia thanh)) hai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((nang ma) OR (nang cao)) hoi. hieu va cam tu ((va thanh) or (gia thanh)) hai cuu tre".
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang ma) OR (nang cao)) hoi. hieu va cam tu ((va thanh) or (gia thanh)) hai cuu tre*.