Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
cac xuc » cam xuc, cac nuoc, chat xuc
va hanh » van hanh, va thanh, va danh
ma hoi » xa hoi, ma hoa, me hoi
vi va » vi van, vai va, vu va
thiet » thieu

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 thu nang ((ma hoi) or (mai hoi)). lieu va cac xuc ((va hanh) or (ban hanh)) vi va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu nang ((ma hoi) OR (mai hoi)). lieu va cac xuc ((va hanh) OR (ban hanh)) vi va thiet.
• Adding a wildcard symbol may retrieve word variants: tu sach thu nang ((ma hoi) or (mai hoi)). lieu va cac xuc ((va hanh) or (ban hanh)) vi va thiet*.