Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach thue » sach thu, sach thieu, cach thuc
sach tham » sach nha
hieu va » lieu va, hieu qua
va hoi » xa hoi, va hoc, va hoa
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, duc va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((sach thue) OR (sach tham)) hang va hoi. hieu va cam ((tuc va) or (tuc xa)) hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((sach thue) OR (sach tham)) hang va hoi. hieu va cam ((tuc va) OR (tuc xa)) hanh vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((sach thue) OR (sach tham)) hang va hoi. hieu va cam ((tuc va) or (tuc xa)) hanh vi cua triet".
• Adding a wildcard symbol may retrieve word variants: doc ((sach thue) OR (sach tham)) hang va hoi. hieu va cam ((tuc va) or (tuc xa)) hanh vi cua triet*.