Perhaps you should try some spelling variations:
tuoc may » hoc may, duoc ma, tao may
su sach » so sach, vu sach
van bac » van ban, van bao, dan bac
tinh di » tinh doi, trinh di, tinh da
van hac » van hoc, van ha, van hai
nang xa » nang x, lang xa, nang ma
so sanh » do sanh
cuu tre » cua tre, cau tren, cau treo
v nang » va nang, vu nang, van nang
di cuu » di cau, di cua, dinh cuu

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 (so sanh)) v nang xa hoi. thi ((van bac) OR (van hac)) tuoc may tinh di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sanh)) v nang xa hoi. thi ((van bac) OR (van hac)) tuoc may tinh di cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sanh)) v nang xa hoi. thi ((van bac) OR (van hac)) tuoc may tinh di cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sanh)) v nang xa hoi. thi ((van bac) OR (van hac)) tuoc may tinh di cuu tre*.