Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
hieu hien » bieu hien, dieu hien, chieu chien
nang dai » nang dau, nang tai, lang dai
cua viet » hoa viet, cua vat, cua dieu
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
thanh vi » hanh vi, thanh va, thanh ve
tu sach » thu sach, su sach, te sach
ca viet » va viet, co viet, hoa viet
dai hoi » dai hoc, dai hai, dai moi
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang dai hoi. hieu hien ((cac nuoc) or (cam xuc)) van thanh vi ((cua viet) or (ca viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang dai hoi. hieu hien ((cac nuoc) OR (cam xuc)) van thanh vi ((cua viet) OR (ca viet)).
• Adding a wildcard symbol may retrieve word variants: tu sach y nang dai hoi. hieu hien ((cac nuoc) or (cam xuc)) van thanh vi ((cua viet) or (ca viet))*.