Perhaps you should try some spelling variations:
hanh gian » thanh gian, thanh giang, manh giang
gian cua » gian xu, ban cua
doc sach » hoc sach, toc sach, nuoc sach
van hanh » van thanh, ban hanh, van anh
phan duc » pham duc, phan tu, phan dau
te sach » toc sach
hieu va » lieu va, hieu qua
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
nang ma » tang ma, sang ma, nang cao
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: ((te sach) or (doc sach)) ky nang ma hoi. ((hieu ve) OR (hieu va)) phan duc van hanh gian cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (doc sach)) ky nang ma hoi. ((hieu ve) OR (hieu va)) phan duc van hanh gian cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (doc sach)) ky nang ma hoi. ((hieu ve) OR (hieu va)) phan duc van hanh gian cua tre*".