Perhaps you should try some spelling variations:
ky dang » ky nang, ky danh
dang ma » dang mau, dang mam, dang mat
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
cua tre » cua te, cuu tre, cua triet
tu san » thu san, tu ban, tu can
san ky » sang ky, van ky, dan ky
ma hoi » mai hoi, xa hoi, ma hoa
tuc va » thuc va, truc va, duc va
dan vi » doan vi, don vi, dan 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: tu san ky dang ma hoi. hieu vu cham ((tuc va) or (tuc xa)) dan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky dang ma hoi. hieu vu cham ((tuc va) OR (tuc xa)) dan vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu san ky dang ma hoi. hieu vu cham ((tuc va) or (tuc xa)) dan vi cua tre*.