Perhaps you should try some spelling variations:
thien van » thi van
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, lieu va, hieu ve
sach ky » sac ky, sach y, sach ty
hac dat » hoc dat, tac dat, hoach dat
va tinh » may tinh
tinh vi » trinh vi, tinh voi, tinh va
ma hoi » mai hoi, ma hoa, me hoi
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: thu sach ky nang ((ma hoi) or (xa hoi)). ((hieu van) or (thien van)) hac dat va tinh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ((ma hoi) OR (xa hoi)). ((hieu van) OR (thien van)) hac dat va tinh vi cua vat.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((ma hoi) or (xa hoi)). ((hieu van) or (thien van)) hac dat va tinh vi cua vat*.