Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
cham tuc » nham thuc, pham thuc, tham thuc
nang xa » nang x, lang xa, nang ma
va danh » va dinh, va dan, va hanh
danh ma » anh ma, danh ca, hanh ma
tuc va » thuc va, truc va, tuc xa
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: ((toc sach) or (hoc sinh)) ky nang xa hoi. hieu van cham tuc va danh ma ((cua te) OR (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sinh)) ky nang xa hoi. hieu van cham tuc va danh ma ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (hoc sinh)) ky nang xa hoi. hieu van cham tuc va danh ma ((cua te) OR (cua tu))".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sinh)) ky nang xa hoi. hieu van cham tuc va danh ma ((cua te) OR (cua tu))*.