Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
dang than » dang thanh, sang than, dang tran
bac nuoc » cac nuoc, bach tuoc, hoc nuoc
than cua » nhan cua, thai cua, ban cua
thi van » thi lan, thi hanh, thi nang
va dang » van dang, va nang, va lang
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc ((sac ky) or (sach y)) nang x hoi. thi van ((bac nuoc) OR (sach nuoc)) va dang than cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc ((sac ky) OR (sach y)) nang x hoi. thi van ((bac nuoc) OR (sach nuoc)) va dang than cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc ((sac ky) or (sach y)) nang x hoi. thi van ((bac nuoc) OR (sach nuoc)) va dang than cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc ((sac ky) or (sach y)) nang x hoi. thi van ((bac nuoc) OR (sach nuoc)) va dang than cua tre*.