Perhaps you should try some spelling variations:
cap nuoc » dat nuoc
danh vai » danh sai, danh va, doanh van
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
va danh » va dinh, va dan, va hanh
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
sach o » sach lo, sac o, mach o

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach o) OR (sach y)) lang xa hoi. hieu ve ((cap nuoc) or (hoc nuoc)) va danh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach o) OR (sach y)) lang xa hoi. hieu ve ((cap nuoc) OR (hoc nuoc)) va danh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach o) OR (sach y)) lang xa hoi. hieu ve ((cap nuoc) or (hoc nuoc)) va danh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach o) OR (sach y)) lang xa hoi. hieu ve ((cap nuoc) or (hoc nuoc)) va danh vai cua tre*.