Perhaps you should try some spelling variations:
dua tren » dung tren
luc ngan » luc nganh, luc nhan, luat ngan
hieu van » hieu va, thien van, lieu va
hang vi » hang va, hanh vi, hang di
cam luc » cam xuc, cau luc
van cam » van nam, van lam, van cau
tu sach » thu sach, te sach, tu cach
nang xa » lang xa, nang ma, mang xa
su sach » so sach, vu sach
vi dua » vi du, vi dum, vi lua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) thu ((nang xa) OR (nang x)) hoi. hieu van cam luc ngan hang vi dua tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) thu ((nang xa) or (nang x)) hoi. hieu van cam luc ngan hang vi dua tren~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) thu ((nang xa) or (nang x)) hoi. hieu van cam luc ngan hang vi dua tren*.