Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
toc sach » hoc sach, doc sach, thuoc sach
thanh vi » hanh vi, thanh va, thanh ve
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
cam duc » cao duc, pham duc, nam duoc
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang

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

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