Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
duc ban » duc tan, duc van, dua ban
cua tre » cuu tre, cua triet, dua tren
van lam » van nam
lam duc » lam duoc, pham duc, nam duoc
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
cua te » cua tu

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 ((ky lang) or (ky dang)) xa hoi. hieu van lam duc ban thanh vai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu van lam duc ban thanh vai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) or (ky dang)) xa hoi. hieu van lam duc ban thanh vai ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) or (ky dang)) xa hoi. hieu van lam duc ban thanh vai ((cua tre) OR (cua te))*.