Perhaps you should try some spelling variations:
sach tham » sach nha
manh hanh » xanh hanh, danh thanh, minh thanh
duc manh » suc manh, duc anh, duc minh
cua viet » ca viet, hoa viet, cua vat
cao hoi » cau hoi, co hoi, cao hoc
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach y) or (sach tham)) nang cao hoi. hieu ve pham duc manh hanh vi ((cua viet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sach tham)) nang cao hoi. hieu ve pham duc manh hanh vi ((cua viet) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sach tham)) nang cao hoi. hieu ve pham duc manh hanh vi ((cua viet) or (cuu tre))*.