Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty hang » ly hang, ty xang, thi hang
hieu ve » hieu va, hieu van
va hoi » xa hoi, va hoc, va hoa
ve cam » ve cham, ve cac, va cam
xac va » tac va, ac va, bac va
cua te » cua tu
cua su » qua su

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty hang va hoi. hieu ve cam ((xac va) OR (thuc vat)) hanh vi ((cua te) OR (cua su))~.
• Adding a wildcard symbol may retrieve word variants: su sach ty hang va hoi. hieu ve cam ((xac va) or (thuc vat)) hanh vi ((cua te) or (cua su))*.