Perhaps you should try some spelling variations:
tham nuoc » thay nuoc, thoat nuoc, nha nuoc
cuoc tre » cuoc tro, nuoc tren, duoc tren
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
hanh lai » hanh lam, thanh lap, thanh loi
van tham » van thanh, van tuan, van chat
sach ty » sach y, sach tu, sach thu
cao hoi » cau hoi, cao hoc, tao hoi
ty nang » ky nang, ty xang, ty hang
te sach » toc sach
co hoi » co hoc, co loi

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 ty nang ((cao hoi) or (co hoi)). hieu van tham nuoc va ((hanh lai) OR (hanh tai)) cuoc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((cao hoi) OR (co hoi)). hieu van tham nuoc va ((hanh lai) OR (hanh tai)) cuoc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ((cao hoi) or (co hoi)). hieu van tham nuoc va ((hanh lai) OR (hanh tai)) cuoc tre".
• Adding a wildcard symbol may retrieve word variants: te sach ty nang ((cao hoi) or (co hoi)). hieu van tham nuoc va ((hanh lai) OR (hanh tai)) cuoc tre*.