Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
cac dai » cac dan, cac bai, can dai
cac dat » cac dan, cai dat, cac dac
sach ky » sac ky, sach y, sach kem
nang ma » tang ma, sang ma, nang cao
sach ty » sach y, sach tu, sach thu
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: thu ((sach ky) or (sach ty)) nang ma hoa. hieu van ((cac dat) OR (cac dai)) va hanh di cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sach ty)) nang ma hoa. hieu van ((cac dat) OR (cac dai)) va hanh di cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sach ty)) nang ma hoa. hieu van ((cac dat) OR (cac dai)) va hanh di cua vat".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sach ty)) nang ma hoa. hieu van ((cac dat) OR (cac dai)) va hanh di cua vat*.