Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
cao luc » bao luc, cao duc, cao suc
xang xa » mang xa, ang xa, dang xay
hang vi » hang va, hanh vi, hang di
lang xa » lang ha, dang xay, lang van
hieu ve » hieu van
va hang » van hang, va nang, va lang
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
vi cua » vai cua, di cua
luc va » duc va, tuc va, loc va
cua tu » cua tuc, cua su, cua cu

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 ((xang xa) OR (lang xa)) hoi. ((hieu ve) or (hieu va)) cao luc va hang vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ty ((xang xa) OR (lang xa)) hoi. ((hieu ve) OR (hieu va)) cao luc va hang vi cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ty ((xang xa) OR (lang xa)) hoi. ((hieu ve) or (hieu va)) cao luc va hang vi cua tu".
• Adding a wildcard symbol may retrieve word variants: hoc sach ty ((xang xa) OR (lang xa)) hoi. ((hieu ve) or (hieu va)) cao luc va hang vi cua tu*.