Perhaps you should try some spelling variations:
thanh hoi » thanh hoai, thanh hoa, thanh hai
van thanh » ban thanh, van tuan
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
duc van » duc va, duc tan, duc manh
cua tre » cua te, cua triet, dua tren
cam duc » cam xuc, cao duc, pham duc
van cam » van nam, van lam, van cau
ty nang » ty xang, ty hang, ly nang
cuu tre » cau tren, cau treo

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

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