Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
kho tang » cao tang
cham duc » pham duc, cham soc, pham duy
tu sach » thu sach, te sach, tu cach
va cham » va chat, va tham
vai cua » dai cua, hai cua, lai cua
duc van » duc va, duc tan, duc manh
hieu va » lieu va, hieu qua
tang ma » mang may, tang van
su sach » so sach, vu sach
ma hoi » mai hoi, xa hoi, ma hoa
vi 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: ((tu sach) or (su sach)) kho tang ma hoi. hieu va cham duc van hanh ((vi cua) OR (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) kho tang ma hoi. hieu va cham duc van hanh ((vi cua) OR (vai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) kho tang ma hoi. hieu va cham duc van hanh ((vi cua) OR (vai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) kho tang ma hoi. hieu va cham duc van hanh ((vi cua) OR (vai cua)) tre*.