Perhaps you should try some spelling variations:
may thoi » gay thoi, may thi, tay thoi
hoc duoc » hoc nuoc, hoa duoc, hoc dung
cua tre » cua te, cuu tre, cua triet
ky mang » ky nang, ky dang, ky tang
ke mang » ke nang, ke trang
hieu ve » hieu va, hieu van
va tinh » may tinh
vi cua » vai cua, di cua
vu sac » vu sach, vu san, va sac
va dan » ca dan, va dao, va dau
ve hoc » te hoc, va hoc, vi hoc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: vu sac ((ky mang) OR (ke mang)) may thoi. hieu ve hoc duoc ((va dan) OR (va tinh)) vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sac ((ky mang) OR (ke mang)) may thoi. hieu ve hoc duoc ((va dan) or (va tinh)) vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: vu sac ((ky mang) OR (ke mang)) may thoi. hieu ve hoc duoc ((va dan) or (va tinh)) vi cua tre*.