Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
sach thi » sach thu, sach thieu, sach tham
hanh lai » hanh lam, hanh tai, thanh lap
sach tai » sach bai, sach tham, sach dao
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
hanh xa » hanh va, hanh ma, hanh xu
ve cam » ve cham, ve cac, va cam
tuc va » truc va, tuc xa, duc va
lai va » loai va, mai va, dai va

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

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