Perhaps you should try some spelling variations:
dinh dat » dinh ket, dinh van, dinh lam
dinh dai » sinh dai, dinh dao, dinh tai
thuc dan » thuc hanh, hoc dan, thuc vat
su sach » so sach, vu sach
ve cham » va cham, ve chat, vu cham
tang ma » mang may, tang van
y tang » ky tang, 6 tang, 7 tang
ve cam » ve cac, va cam, ve cai
ma hoi » mai hoi, xa hoi, ma hoa
cua te » cua tu

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