Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
va hanh » van hanh, va thanh, va danh
cam tuc » cam xuc, cam tu, nam thuc
hieu va » lieu va, hieu qua
hieu ve » hieu van
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
ma hoi » mai hoi, xa hoi, ma hoa
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua
cua te » cua tu

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 (thu sach)) ky tang ma hoi. ((hieu ve) OR (hieu va)) cam tuc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky tang ma hoi. ((hieu ve) OR (hieu va)) cam tuc va hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ky tang ma hoi. ((hieu ve) OR (hieu va)) cam tuc va hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky tang ma hoi. ((hieu ve) OR (hieu va)) cam tuc va hanh vi cua te*.