Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
va hanh » van hanh, va thanh, va danh
hai dat » cai dat, hoi dat, hai dan
sach ty » sach y, sach tu, sach thu
van hai » van ha, van chat, van hanh
sach ky » sac ky, sach y, sach kem
mai hoi » mai khoi, dai hoi, lai hoi
vi cua » vai cua, di cua
ma hoi » xa hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sach ty)) nang ((ma hoi) or (mai hoi)). hieu van hai dat va hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) nang ((ma hoi) OR (mai hoi)). hieu van hai dat va hanh vi cua vat.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach ty)) nang ((ma hoi) or (mai hoi)). hieu van hai dat va hanh vi cua vat*.