Perhaps you should try some spelling variations:
thien van » thi van
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
su sach » so sach, vu sach
cua tre » cua te, cua triet, dua tren
bac tac » bac tai, cac tac, bac thay
van bac » van ban, van bao, van hac
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
cuu tre » cau tren, cau treo
tac va » tac da, tac xa, tuc va

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 ((ky lang) OR (ky tang)) xa hoi. thien van bac tac va thanh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky lang) OR (ky tang)) xa hoi. thien van bac tac va thanh vi ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky lang) OR (ky tang)) xa hoi. thien van bac tac va thanh vi ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky lang) OR (ky tang)) xa hoi. thien van bac tac va thanh vi ((cua tre) or (cuu tre))*.