Perhaps you should try some spelling variations:
manh hanh » xanh hanh, danh thanh, minh thanh
hoc sach » hoc sinh, hoc cac, hoc anh
thu bang » thu ban, chu bang, thu trang
thu hang » thi hang, thuc hanh, thu huong
duc manh » suc manh, duc anh, duc minh
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
lai cua » dai cua, hai cua, thai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ((thu bang) or (thu hang)) xa hoi. hieu va cac duc manh hanh ((lai cua) OR (lai chau)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((thu bang) OR (thu hang)) xa hoi. hieu va cac duc manh hanh ((lai cua) OR (lai chau)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((thu bang) or (thu hang)) xa hoi. hieu va cac duc manh hanh ((lai cua) OR (lai chau)) tre".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((thu bang) or (thu hang)) xa hoi. hieu va cac duc manh hanh ((lai cua) OR (lai chau)) tre*.