Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
vat thanh » dat thanh, gat thanh, tat thanh
cua triet » cua viet, su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, dua tren
va nam » ha nam, va nay

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 nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh doi ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh doi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh doi ((cua tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh doi ((cua tre) or (cua triet))*.