Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
dao dai » dat dai, dao dan, tao dai
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu van
va dao » ca dao
cua te » cua tu
sach 7 » sach y, sach 2
ma hoi » mai hoi, xa hoi, me hoi
7 tang » 6 tang

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 7 tang ((ma hoi) OR (ma hoa)). ((hieu ve) or (hieu va)) cam thuc va dao dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach 7 tang ((ma hoi) OR (ma hoa)). ((hieu ve) OR (hieu va)) cam thuc va dao dai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach 7 tang ((ma hoi) OR (ma hoa)). ((hieu ve) or (hieu va)) cam thuc va dao dai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach 7 tang ((ma hoi) OR (ma hoa)). ((hieu ve) or (hieu va)) cam thuc va dao dai cua te*.