Perhaps you should try some spelling variations:
toc cach » hoc cach, toc sach, truoc cach
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cam thu » nam thu, cac thu, ca thu
cach tu » cach thuc
tu nang » tru nang, tu nong, tu nano
cuu tre » cua tre, cau treo
va nang » van nang, da nang, kha nang
va cam » va cham, va cac, va cao

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc cach tu nang xa hoi. hieu va cam thu ((va nang) or (cam nang)) doi ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc cach tu nang xa hoi. hieu va cam thu ((va nang) OR (cam nang)) doi ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc cach tu nang xa hoi. hieu va cam thu ((va nang) or (cam nang)) doi ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: toc cach tu nang xa hoi. hieu va cam thu ((va nang) or (cam nang)) doi ((cuu tre) OR (cau tren))*.