Perhaps you should try some spelling variations:
tinh voi » trinh voi, tinh doi, binh voi
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
my tinh » may tinh, ly tinh, mo tinh
voi cua » hoi cua, doi cua, moi cua
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, me hoi
ve hoc » te hoc, va hoc, vi hoc

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: vu sach ky nang ((ma hoi) OR (ma hoa)). hieu ve hoc (nuoc OR ngoc) my tinh voi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang ((ma hoi) or (ma hoa)). hieu ve hoc (nuoc OR ngoc) my tinh voi cua tre~".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((ma hoi) or (ma hoa)). hieu ve hoc (nuoc OR ngoc) my tinh voi cua tre*.