Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
su sach » so sach, vu sach
qua hai » qua hoat
hai luc » hai cuc, khai luoc, nhan luc
va vanh » va van, va danh, va hanh
cua tuc » cua duc, cua thuoc, luat tuc
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
luc va » duc va, tuc va, loc va
cua tu » cua su, cua cu, cua vu
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang o hoi. hieu qua hai luc va vanh dai ((cua te) or (((cua tu) OR (cua tuc))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang o hoi. hieu qua hai luc va vanh dai ((cua te) OR (((cua tu) OR (cua tuc))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang o hoi. hieu qua hai luc va vanh dai ((cua te) or (((cua tu) OR (cua tuc))))*".