Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
cau treo » cau theo, cau tren, cau triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
cac luc » coc luc, cac nuoc, cac cuoc
cau luc » cau truc, cau phuc
va dao » ca dao
dao vi » dao voi, dao ve, dao va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang x ho. hieu va ((cac luc) OR (cau luc)) va dao vi ((cau treo) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x ho. hieu va ((cac luc) OR (cau luc)) va dao vi ((cau treo) OR (dau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x ho. hieu va ((cac luc) OR (cau luc)) va dao vi ((cau treo) or (dau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x ho. hieu va ((cac luc) OR (cau luc)) va dao vi ((cau treo) or (dau tren))*.