Perhaps you should try some spelling variations:
tu sach » thu sach, te sach, tu cach
va hanh » van hanh, va thanh, va danh
nang ma » tang ma, sang ma, nang cao
su sach » so sach, vu sach
ma hoi » mai hoi, xa hoi, ma hoa
ve cam » ve cham, va cam, ve cai
ve cac » va cac, vien cac
xuc va » duc va, tuc va, luc va
vi cua » vai 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)) ky nang ma hoi. hieu ((ve cam) OR (ve cac)) xuc va hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang ma hoi. hieu ((ve cam) OR (ve cac)) xuc va hanh vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang ma hoi. hieu ((ve cam) OR (ve cac)) xuc va hanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky nang ma hoi. hieu ((ve cam) OR (ve cac)) xuc va hanh vi cua vat*.