Perhaps you should try some spelling variations:
co viet » so viet, o viet, hoc viet
tinh vi » trinh vi, tinh voi, tinh va
va tinh » may tinh
duoc va » nuoc va, duc va, duoc ma
nang xa » nang x, lang xa, nang ma
va nay » va ngay, va cay
sac ky » cac ky, sai ky
va nam » van nam, ha nam
vi co » vi con, voi co, vi mo

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) or (sach y)) nang xa hoi. hieu ((va nam) or (va nay)) duoc va tinh vi co viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sac ky) OR (sach y)) nang xa hoi. hieu ((va nam) OR (va nay)) duoc va tinh vi co viet.
• Adding a wildcard symbol may retrieve word variants: su ((sac ky) or (sach y)) nang xa hoi. hieu ((va nam) or (va nay)) duoc va tinh vi co viet*.