Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
lang xa » lang ha, dang xay, lang van
va cham » va chat, va tham
sach ky » sac ky, sach y, sach ty
tinh di » tinh doi, trinh di, tinh da
sai ky » sac ky
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
di cau » da cau, diem cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((sach ky) or (sai ky)) lang xa hoi. lieu va cham ((luc va) OR (tuc va)) tinh di cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((sach ky) OR (sai ky)) lang xa hoi. lieu va cham ((luc va) OR (tuc va)) tinh di cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((sach ky) or (sai ky)) lang xa hoi. lieu va cham ((luc va) OR (tuc va)) tinh di cau tren".
• Adding a wildcard symbol may retrieve word variants: hoc ((sach ky) or (sai ky)) lang xa hoi. lieu va cham ((luc va) OR (tuc va)) tinh di cau tren*.