Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
va hanh » va thanh, va danh, ban hanh
tai cua » thai cua, tai cuc, tri cua
van cam » van nam, van lam, van cau
cam tuc » cam xuc, cam tu, nam thuc
nang xa » nang x, lang xa, nang ma
cua te » cua tu

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 (doc sach)) ky nang xa hoi. hieu van cam tuc ((va hanh) OR (van hanh)) tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ky nang xa hoi. hieu van cam tuc ((va hanh) OR (van hanh)) tai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (doc sach)) ky nang xa hoi. hieu van cam tuc ((va hanh) OR (van hanh)) tai cua te".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (doc sach)) ky nang xa hoi. hieu van cam tuc ((va hanh) OR (van hanh)) tai cua te*.