Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
va thanh » gia thanh, ban thanh, va tinh
va hanh » van hanh, va danh, ban hanh
hieu ve » hieu va, hieu van
su sach » so sach, vu sach
cau luc » cau truc, cau phuc
nang xa » lang xa, nang ma, mang xa
ve cau » ke cau, va cau, ve cac
vi va » vi van, vai va, vu va

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