Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
hanh tai » thanh tai, hang tai, han tai
hieu ve » hieu va, hieu van
su sach » so sach, vu sach
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
ve cau » ke cau, va cau, ve cac
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
tai va » thai va, mai va, tri 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 (lang xa)) hoi. hieu ve cau ((luc va) OR (tuc va)) hanh tai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y ((nang xa) OR (lang xa)) hoi. hieu ve cau ((luc va) OR (tuc va)) hanh tai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y ((nang xa) or (lang xa)) hoi. hieu ve cau ((luc va) OR (tuc va)) hanh tai va triet".
• Adding a wildcard symbol may retrieve word variants: su sach y ((nang xa) or (lang xa)) hoi. hieu ve cau ((luc va) OR (tuc va)) hanh tai va triet*.