Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh dai » hanh tai, hanh dao, vanh dai
sach ty » sach tu, sach thu, xach tay
nang ma » tang ma, sang ma, nang cao
xuc van » duc van, luc van, vuc van
ma hoi » mai hoi, xa hoi, ma hoa
ve cam » ve cham, ve cac, ve cai
va cam » va cham, va cac, va cao

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: su ((sach ty) OR (sach y)) nang ma hoi. hieu ((ve cam) OR (va cam)) xuc van hanh dai cua vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach y)) nang ma hoi. hieu ((ve cam) or (va cam)) xuc van hanh dai cua vat~".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach y)) nang ma hoi. hieu ((ve cam) or (va cam)) xuc van hanh dai cua vat*.