Perhaps you should try some spelling variations:
thuc may » thuc day, truc may, phuc may
cac thuc » cach thuc, cac thu, can thuc
hoc sach » hoc sinh, hoc cac, hoc anh
nang van » dang van, tang van, lang van
su sach » vu sach
tinh va » tich va, trinh van, trinh vat
hieu ve » hieu va, hieu van
van hoi » van hoa, van hoc, van hoe
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
ve cac » va cac, vien cac
va cua » va chua, via cua, ca cua

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 sach))) or (hoc sach)) ky nang van hoi. hieu ve cac thuc may tinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((su sach) OR (so sach))) OR (hoc sach)) ky nang van hoi. hieu ve cac thuc may tinh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((su sach) OR (so sach))) or (hoc sach)) ky nang van hoi. hieu ve cac thuc may tinh va cua tre".
• Adding a wildcard symbol may retrieve word variants: ((((su sach) OR (so sach))) or (hoc sach)) ky nang van hoi. hieu ve cac thuc may tinh va cua tre*.