Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
hoc cac » hoc cao
tu hung » tu chung, tu nhung, tu vung
hung xa » chung xa, huong xa, hung ha
ve pham » v pham, ve phan, ve phat
duc van » duc va, duc tan, duc manh
hanh va » hang va, hanh vi
cuu tre » cua tre, cau tren, cau treo
va cuu » va cau, va chu, va huu

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

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