Perhaps you should try some spelling variations:
xanh hanh » danh thanh, ban hanh, van hanh
dua tren » dung tren
sach thu » sach thue, sach thieu, sach tham
duc xanh » duc anh, duc manh, duc hanh
va pham » van pham, va phat, va phap
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
tang ma » mang may, tang van
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa

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 ky) OR (sach thu)) tang ma hoi. hieu va pham duc xanh hanh vi ((dua tren) OR (cuu tre))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sach thu)) tang ma hoi. hieu va pham duc xanh hanh vi ((dua tren) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sach thu)) tang ma hoi. hieu va pham duc xanh hanh vi ((dua tren) OR (cuu tre))*.