Perhaps you should try some spelling variations:
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
cac dac » cac dan, cac dai, cac bac
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cua tre » cua te, cuu tre, cua triet
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
dac va » duc va, day va, dat va
vi cua » vai cua, di 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 sac ky ((nang x) or (nang ma)) hoi. hieu va cac dac va danh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky ((nang x) OR (nang ma)) hoi. hieu va cac dac va danh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sac ky ((nang x) or (nang ma)) hoi. hieu va cac dac va danh vi cua tre*.