Perhaps you should try some spelling variations:
hoc ngoc » hoc nuoc, ho ngoc, loc ngoc
dong cua » dung cua, cong cua, huong cua
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
ngoc va » nuoc va, ngoc ha, goc va
va hanh » van hanh, va thanh, va danh
y nang » ly nang, v nang, may nang
ve hoc » te hoc, va hoc, vi hoc
di cua » dai cua, doi cua, de 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: su sach ((y nang) OR (ky nang)) xa hoi. hieu ve hoc ngoc va hanh ((di cua) OR (dong cua)) te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y nang) OR (ky nang)) xa hoi. hieu ve hoc ngoc va hanh ((di cua) or (dong cua)) te~".
• Adding a wildcard symbol may retrieve word variants: su sach ((y nang) OR (ky nang)) xa hoi. hieu ve hoc ngoc va hanh ((di cua) or (dong cua)) te*.