Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
thanh vai » thanh hai, thanh van, thanh tai
cua triet » cua viet, su triet, va triet
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
vai cua » dai cua, hai cua, lai cua
sac ky » cac ky, sai ky
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: su ((sach ky) or (sac ky)) nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh vai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh vai cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) or (sac ky)) nang xa hoi. hieu ((va nam) OR (van nam)) thuc vat thanh vai cua triet*".