Perhaps you should try some spelling variations:
nang mai » nang ma, nang tai, lang mai
hanh di » hanh vi, hanh de, hang di
thue va » thuc va, thuyet va, thuc vat
sach ky » sach y, sach ty, sach kem
hieu le » hieu ve, hieu he, hieu ly
mai hoi » mai khoi, dai hoi, lai hoi
le nam » ly nam, he nam, le na
thu va » thuc va, tu va, thu ha
sac ky » cac ky, sai ky
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 ky) OR (sac ky)) nang mai hoi. hieu le nam ((thu va) or (thue va)) hanh di cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) nang mai hoi. hieu le nam ((thu va) OR (thue va)) hanh di cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sac ky)) nang mai hoi. hieu le nam ((thu va) or (thue va)) hanh di cua vat".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) OR (sac ky)) nang mai hoi. hieu le nam ((thu va) or (thue va)) hanh di cua vat*.