Perhaps you should try some spelling variations:
chat nuoc » nhat nuoc, khat nuoc, thoat nuoc
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van chat » cao chat
ty nang » ty xang, ty hang, ly nang
cao hoi » cau hoi, co hoi, cao hoc
va hanh » van hanh, va thanh, va danh
lai cua » dai cua, hai cua, thai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ty nang) or (ky nang)) cao hoi. hieu van chat nuoc va hanh ((lai cua) OR (lai chau)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ty nang) OR (ky nang)) cao hoi. hieu van chat nuoc va hanh ((lai cua) OR (lai chau)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((ty nang) or (ky nang)) cao hoi. hieu van chat nuoc va hanh ((lai cua) OR (lai chau)) tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ((ty nang) or (ky nang)) cao hoi. hieu van chat nuoc va hanh ((lai cua) OR (lai chau)) tre*.