Perhaps you should try some spelling variations:
ve triet » va trien, su triet
thuc dan » thuc hanh, hoc dan, thuc vat
hanh dai » hanh tai, hanh dao, vanh dai
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc day
hieu ve » hieu va, hieu van
xang xa » lang xa, mang xa, ang xa
su sach » so sach, vu sach
dai ve » dap ve, dau ve, 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: su sach ty xang xa hoi. ((hieu ve) or (hieu qua)) cau ((thuc va) or (thuc dan)) hanh dai ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty xang xa hoi. ((hieu ve) OR (hieu qua)) cau ((thuc va) OR (thuc dan)) hanh dai ve triet.
• Adding a wildcard symbol may retrieve word variants: su sach ty xang xa hoi. ((hieu ve) or (hieu qua)) cau ((thuc va) or (thuc dan)) hanh dai ve triet*.