Perhaps you should try some spelling variations:
doc thuc » hoc thuc, do thuc, hoc thuoc
va tinh » may tinh
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
coc tuc » coc luc, hoc thuc, hoc truc
ca cua » co cua
va cua » va chua, via cua, ma cua
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky

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 tang xa hoi. hieu va ((coc tuc) or (doc thuc)) va tinh ((va cua) or (ca cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky tang xa hoi. hieu va ((coc tuc) OR (doc thuc)) va tinh ((va cua) OR (ca cua)) tre.
• Adding a wildcard symbol may retrieve word variants: su sac ky tang xa hoi. hieu va ((coc tuc) or (doc thuc)) va tinh ((va cua) or (ca cua)) tre*.