Perhaps you should try some spelling variations:
ve triet » va trien, su triet
va triet » va thiet, va trien, cua triet
hanh tai » thanh tai, hang tai, han tai
dang xay » dang van, van xay
cau luc » cau truc, cau phuc
va hanh » van hanh, va thanh, va danh
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
luc va » duc va, tuc va, loc va
ve cau » ke cau, va cau, ve cac

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 y ((nang xa) or (dang xay)) hoi. hieu ve cau luc va hanh tai ((va triet) OR (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y ((nang xa) OR (dang xay)) hoi. hieu ve cau luc va hanh tai ((va triet) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y ((nang xa) or (dang xay)) hoi. hieu ve cau luc va hanh tai ((va triet) OR (ve triet))".
• Adding a wildcard symbol may retrieve word variants: su sach y ((nang xa) or (dang xay)) hoi. hieu ve cau luc va hanh tai ((va triet) OR (ve triet))*.