Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
cua tre » cua te, cuu tre, cua triet
duc ban » duc tan, duc van, duc man
tang ma » mang may, tang van
dua ban » dia ban, cua ban, qua ban
hieu ve » hieu va, hieu van
sac kho » cac khoi, dac khoa, cac khoa
ma hoi » mai hoi, xa hoi, ma hoa
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sac kho) OR (suc khoe)) tang ma hoi. hieu ve cam ((duc ban) or (dua ban)) thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sac kho) OR (suc khoe)) tang ma hoi. hieu ve cam ((duc ban) OR (dua ban)) thanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sac kho) OR (suc khoe)) tang ma hoi. hieu ve cam ((duc ban) or (dua ban)) thanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sac kho) OR (suc khoe)) tang ma hoi. hieu ve cam ((duc ban) or (dua ban)) thanh dai cua tre*.