Perhaps you should try some spelling variations:
nhanh thang » nhanh thanh, nhanh quang, hanh trang
hinh thai » sinh thai, tinh thai, dinh thi
nuoc van » nuoc va, nuoc san, luoc van
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
nang co » nang cao, nang doc, nang noi
nang o » nang ho, nang ro, nang x
ve hoc » te hoc, va hoc, vi hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((nang o) or (nang co)) hai. hieu ve hoc nuoc van ((nhanh thang) or (hinh thai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang o) OR (nang co)) hai. hieu ve hoc nuoc van ((nhanh thang) OR (hinh thai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang o) or (nang co)) hai. hieu ve hoc nuoc van ((nhanh thang) or (hinh thai)) cua tre*.