Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va chao » va cao, va chat, va cham
va danh » va dinh, va dan, va hanh
va tinh » may tinh
so viet » hoc viet
hai so » dai so, tai so, thai son

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach thu nang xa hoi. hieu va chao xu ((va danh) or (va tinh)) hai so viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu nang xa hoi. hieu va chao xu ((va danh) OR (va tinh)) hai so viet.
• Adding a wildcard symbol may retrieve word variants: su sach thu nang xa hoi. hieu va chao xu ((va danh) or (va tinh)) hai so viet*.