Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang ro » nang co, nang ho, nang ra
van cau » van dau, van hau, van chat
cau duc » cao duc, cau luc, chu duc
ro hai » co hai, o hai, so hai
lam so » lam son, nam so, lam co
ham so » nam so, cham soc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang ro hai. hieu van cau duc va thanh ((lam so) or (ham so)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ro hai. hieu van cau duc va thanh ((lam so) OR (ham so)) triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ro hai. hieu van cau duc va thanh ((lam so) or (ham so)) triet*.