Perhaps you should try some spelling variations:
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
sach ly » sach y, sach lo, sach ty
ly nang » ky nang, ly hang, ly vang
hieu ve » hieu va, hieu van
cac duc » cao duc, cac dac, cac nuoc
vai cua » hai cua, lai cua, bai cua
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ly nang x hoi. hieu ve ((cac duc) or (cac du)) ban hanh ((vai cua) OR (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ly nang x hoi. hieu ve ((cac duc) OR (cac du)) ban hanh ((vai cua) OR (dai cua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ly nang x hoi. hieu ve ((cac duc) or (cac du)) ban hanh ((vai cua) OR (dai cua)) tre*".