Perhaps you should try some spelling variations:
hanh doi » thanh doi, hanh noi, hang doi
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
doi cua » dai cua, hoi cua
sai ky » sac ky
ve hoc » te hoc, va hoc, vi hoc
cua te » cua tu
x hoi » xa hoi, o hoi, x ho
nuoc » quoc, duoc, ngoc

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: thuoc ((sai ky) OR (sach ty)) nang x hoi. hieu ve hoc nuoc va hanh doi cua te~.
• Adding a wildcard symbol may retrieve word variants: thuoc ((sai ky) or (sach ty)) nang x hoi. hieu ve hoc nuoc va hanh doi cua te*.