Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, co hoi, cao hoc
van cam » van nam, van lam, van cau
va hanh » van hanh, va thanh, va danh
sai ky » sac ky
xuc va » duc va, tuc va, luc va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so ((sach ky) or (sai ky)) nang cao hoi. hieu van cam xuc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach ky) OR (sai ky)) nang cao hoi. hieu van cam xuc va hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: so ((sach ky) or (sai ky)) nang cao hoi. hieu van cam xuc va hanh vi cua viet*.