Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
thai cua » than cua, tai cuc, tri cua
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
hoc sach » hoc sinh, hoc cac, hoc anh
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
nam tuc » nam thuc, nam truc, nam tu
tuc van » thuc van, truc van, tuc va
tai cua » tai cuc, tri cua, dai cua

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) or (hoc sach)) ky dang xa hoi. hieu van nam tuc van hanh ((tai cua) OR (thai cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ky dang xa hoi. hieu van nam tuc van hanh ((tai cua) OR (thai cua)) te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (hoc sach)) ky dang xa hoi. hieu van nam tuc van hanh ((tai cua) OR (thai cua)) te*".