Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach ty » sach y, sach tu, sach thu
hang xa » hoang xa, hang ca, lang xa
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
tuc may » truc may, tu may, tuc xay
va va » va van, va vai, va vat

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 ty ((hang xa) OR (hang va)) hoi. hieu va cac tuc may tinh ((va va) or (va vua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty ((hang xa) OR (hang va)) hoi. hieu va cac tuc may tinh ((va va) OR (va vua)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty ((hang xa) OR (hang va)) hoi. hieu va cac tuc may tinh ((va va) or (va vua)) viet".
• Adding a wildcard symbol may retrieve word variants: thu sach ty ((hang xa) OR (hang va)) hoi. hieu va cac tuc may tinh ((va va) or (va vua)) viet*.