Perhaps you should try some spelling variations:
te sach » toc sach
cao hoi » cau hoi, co hoi, tao hoi
cao hoc » co hoc, cho hoc, chat hoc
hieu su » hieu sau, tieu su, hieu so
dau cua » day cua, cau cua, dan cua
y nang » ky nang, ly nang, v nang
su cam » su nam, su cao, su can
xuc va » duc va, tuc va, luc va
va dan » ca dan, va dao, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y nang ((cao hoi) or (cao hoc)). hieu su cam xuc va dan ((dau cua) or (dai cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((cao hoi) OR (cao hoc)). hieu su cam xuc va dan ((dau cua) OR (dai cua)) te.
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((cao hoi) or (cao hoc)). hieu su cam xuc va dan ((dau cua) or (dai cua)) te*.