Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
nang xa » nang x, nang ma, mang xa
xuc va » duc va, tuc va, luc va
va dan » ca dan, va dao, va dau
tu cuu » tu huu, tu cua, tu chu
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y ((nang xa) OR (lang xa)) hoi. hieu va cam xuc va dan ((du cuu) or (tu cuu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y ((nang xa) OR (lang xa)) hoi. hieu va cam xuc va dan ((du cuu) OR (tu cuu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y ((nang xa) OR (lang xa)) hoi. hieu va cam xuc va dan ((du cuu) or (tu cuu)) tre".
• Adding a wildcard symbol may retrieve word variants: toc sach y ((nang xa) OR (lang xa)) hoi. hieu va cam xuc va dan ((du cuu) or (tu cuu)) tre*.