Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
hieu van » hieu va, thien van, lieu va
dang mau » dong mau, dang van, dang su
duc tre » duoc tren, duc tien
han tai » hang tai, nhan tai, van tai
cam luc » cam xuc, cau luc
hieu ve » hieu va
mau hoi » cau hoi, mai hoi, mau ho
ky dang » ky nang, ky danh
sac ky » cac ky, sai ky
luc va » duc va, tuc va, loc va
su sac » su sach, su cac, su xac

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: su sac ky dang mau hoi. ((hieu ve) OR (hieu van)) cam luc va ((thanh tai) OR (han tai)) duc tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky dang mau hoi. ((hieu ve) OR (hieu van)) cam luc va ((thanh tai) or (han tai)) duc tre~".
• Adding a wildcard symbol may retrieve word variants: su sac ky dang mau hoi. ((hieu ve) OR (hieu van)) cam luc va ((thanh tai) or (han tai)) duc tre*.