Perhaps you should try some spelling variations:
cua triet » su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
thanh va » thanh van, hanh va, thanh ha
cua viet » ca viet, hoa viet, cua vat
sach ty » sach y, sach tu, sach thu
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
duc ban » duc van, dua ban, duc man

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 ty lang xa hoi. hieu va cac ((duc ban) OR (duc tan)) thanh va ((cua triet) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty lang xa hoi. hieu va cac ((duc ban) OR (duc tan)) thanh va ((cua triet) OR (cua viet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty lang xa hoi. hieu va cac ((duc ban) OR (duc tan)) thanh va ((cua triet) or (cua viet))*".