Perhaps you should try some spelling variations:
dien cua » dieu cua, dien cu, tien cua
dien cuc » dien tu, dieu cua, vien cac
hieu ve » hieu va, hieu van
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
nang o » nang co, nang ho, nang ro
ve cau » ke cau, va cau, ve cac
luc va » tuc va, loc va
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: te sac ky nang o hoi. hieu ve cau ((luc va) or (duc va)) hanh ((dien cua) OR (dien cuc)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang o hoi. hieu ve cau ((luc va) OR (duc va)) hanh ((dien cua) OR (dien cuc)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky nang o hoi. hieu ve cau ((luc va) or (duc va)) hanh ((dien cua) OR (dien cuc)) viet".
• Adding a wildcard symbol may retrieve word variants: te sac ky nang o hoi. hieu ve cau ((luc va) or (duc va)) hanh ((dien cua) OR (dien cuc)) viet*.