Perhaps you should try some spelling variations:
duy vatn » duy van, duy can, quy van
su sach » so sach, vu sach
hanh di » hanh vi, hanh de, hang di
ve pham » vi pham, v pham, ve phan
sach ly » sach y, sach lo, sach ty
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
sang ma » tang ma, nang ma, sang tao
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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 ly ((nang xa) or (sang ma)) hoi. hieu ve pham ((duy vat) or (duy vatn)) hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly ((nang xa) OR (sang ma)) hoi. hieu ve pham ((duy vat) OR (duy vatn)) hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ly ((nang xa) or (sang ma)) hoi. hieu ve pham ((duy vat) or (duy vatn)) hanh di cua tre*.