Perhaps you should try some spelling variations:
cua triet » su triet, va triet
truc van » truc va, thuc van, truc ban
cua viet » ca viet, hoa viet, cua vat
co sach » bo sach, cuon sach, hoc sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
qua hai » qua hoat
tuc van » thuc van, tuc va, duc van

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

• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ky dang xa hoi. hieu qua hai ((tuc van) OR (truc van)) hanh vi ((cua triet) OR (cua viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach ky dang xa hoi. hieu qua hai ((tuc van) or (truc van)) hanh vi ((cua triet) OR (cua viet))~".
• Adding a wildcard symbol may retrieve word variants: co sach ky dang xa hoi. hieu qua hai ((tuc van) or (truc van)) hanh vi ((cua triet) OR (cua viet))*.