Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
hieu van » hieu va, thien van, lieu va
sach ty » sach y, sach tu, sach thu
va hanh » van hanh, va thanh, va danh
cac dat » cac dan, cac dai, cac dac
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
ty nang » ky nang, ty xang, ty hang
vai cua » dai cua, hai cua, lai 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 ty nang ((ma hoi) or (mai hoi)). hieu van ((cac dat) or (cai dat)) va hanh vai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((ma hoi) OR (mai hoi)). hieu van ((cac dat) OR (cai dat)) va hanh vai cua vat.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((ma hoi) or (mai hoi)). hieu van ((cac dat) or (cai dat)) va hanh vai cua vat*.