Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
lang xa » lang ha, dang xay, lang van
va hanh » van hanh, va thanh, va danh
su viet » so viet
vi su » va su, ve su, ki su

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