Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
cac dac » cac dan, cac dai, cac bac
dac van » cac van, dao van, dam van
vai cua » hai cua, lai cua, bai cua

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