Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, cau treo
te sach » toc sach
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, co hoi, cao hoc
hieu va » lieu va, hieu qua
ca tren » cu tren, la tren, co tren
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, duc 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 ky nang cao hoi. hieu va cam ((tuc va) OR (tuc xa)) dan ca ((cau tren) or (ca tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang cao hoi. hieu va cam ((tuc va) OR (tuc xa)) dan ca ((cau tren) OR (ca tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang cao hoi. hieu va cam ((tuc va) OR (tuc xa)) dan ca ((cau tren) or (ca tren))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang cao hoi. hieu va cam ((tuc va) OR (tuc xa)) dan ca ((cau tren) or (ca tren))*.