Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
hieu ke » hieu kem, chieu ke, hieu ky
truc va » thuc va, thuc vat, trung va
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cu tren » tu tren, dua tren
sac ky » sai ky
ma hoi » mai hoi, xa hoi, ma hoa
ke cau » ket cau
vi cu » vi su, vi xu, vi du

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((sach ky) or (((sac ky) or (cac ky)))) nang ma hoi. hieu ke cau truc va danh vi cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((sach ky) OR (((sac ky) OR (cac ky)))) nang ma hoi. hieu ke cau truc va danh vi cu tren.
• Adding a wildcard symbol may retrieve word variants: hoc ((sach ky) or (((sac ky) or (cac ky)))) nang ma hoi. hieu ke cau truc va danh vi cu tren*.