Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua

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

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