Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
cau tren » cu tren, dau tren, ca tren
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
cac luc » cau luc, coc luc, cac nuoc
va doan » va doanh, van doan, va dan
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va
va cau » van cau, va cac, va dau

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 ty ((nang xa) OR (nang ma)) hoi. hieu ve cac luc va doan va cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ty ((nang xa) OR (nang ma)) hoi. hieu ve cac luc va doan va cau tren".
• Adding a wildcard symbol may retrieve word variants: hoc sach ty ((nang xa) OR (nang ma)) hoi. hieu ve cac luc va doan va cau tren*.