Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
phat duc » phan duc, phan duoc, pham duy
hanh vai » hanh vi, hanh va, hanh tai
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua

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 xa hoi. hieu van ((phat duc) or (pham duc)) va hanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu van ((phat duc) OR (pham duc)) va hanh vai cua viet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu van ((phat duc) or (pham duc)) va hanh vai cua viet*.