Perhaps you should try some spelling variations:
doc thuc » hoc thuc, do thuc, hoc thuoc
va tinh » may tinh
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
va chua » vua chua, ca chua, va chu
coc tuc » coc luc, hoc thuc, hoc truc
va cua » via cua, ca cua, ma cua
su xac » pu xac, su cac
xac ky » cac ky, sac ky, bac ky

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 xac ky lang xa hoi. hieu ve ((coc tuc) OR (doc thuc)) va tinh ((va cua) OR (va chua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su xac ky lang xa hoi. hieu ve ((coc tuc) or (doc thuc)) va tinh ((va cua) OR (va chua)) tre~".
• Adding a wildcard symbol may retrieve word variants: su xac ky lang xa hoi. hieu ve ((coc tuc) or (doc thuc)) va tinh ((va cua) OR (va chua)) tre*.