Perhaps you should try some spelling variations:
cap nuoc » dat nuoc
dang xay » dang van, van xay
van hanh » van thanh, ban hanh, van ban
van anh » van thanh, tuan anh, van minh
cua tre » cua te, cuu tre, cua triet
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » lieu va, hieu qua
ky dang » ky nang, ky danh
sac ky » cac ky, sai ky
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky dang xay hoi. hieu va ((cap nuoc) or (hoc nuoc)) ((van hanh) or (van anh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky dang xay hoi. hieu va ((cap nuoc) OR (hoc nuoc)) ((van hanh) OR (van anh)) dai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sac ky dang xay hoi. hieu va ((cap nuoc) or (hoc nuoc)) ((van hanh) or (van anh)) dai cua tre*.