Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
cam truc » cau truc, nam truc, lam truoc
tu sach » su sach, te sach, tu cach
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
tay hoi » tao hoi, tay thai
ve cam » ve cham, ve cac, va cam
va cua » va chua, via cua, ca cua
tay ho » tay co, tay o, tay khao

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