Perhaps you should try some spelling variations:
hanh va » hang va, hanh vi
va chat » van chat, va phat, cao chat
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
cach su » cach tu, hoach su
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
tuc va » thuc va, truc va, duc va
va cua » va chua, via cua, ca 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 ty) OR (cach su)) nang ma hoi. hieu va chat ((tuc va) OR (tuc xa)) hanh va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (cach su)) nang ma hoi. hieu va chat ((tuc va) OR (tuc xa)) hanh va cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (cach su)) nang ma hoi. hieu va chat ((tuc va) OR (tuc xa)) hanh va cua tre*.