Perhaps you should try some spelling variations:
cau tren » cu tren, ca tren, cau treo
dinh vai » dinh van, dinh vi, dinh va
dau tren » dau tien, dat tren, dau tieng
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
sach ky » sach y, sach ty, sach kem
va dinh » van dinh, va kinh, va tinh
sac ky » cac ky, sai ky
va cam » va cham, va cac, va cao
cam o » cham o, cam lo, ca o
o va » do va, so va, co va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam o va dinh vai ((cau tren) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam o va dinh vai ((cau tren) OR (dau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam o va dinh vai ((cau tren) or (dau tren))".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) OR (sac ky)) lang xa hoi. hieu va cam o va dinh vai ((cau tren) or (dau tren))*.