Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
hanh hai » thanh hai, nhanh hai, hang hai
hieu van » hieu va, lieu va, hieu ve
tu quang » vu quang, chu quang, bui quang
va hanh » van hanh, va thanh, va danh
tu xang » ty xang, tu lang, tct xang
hai cua » thai cua, dai cua, hoi cua
soc va » hoc va, loc va, doc va
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((tu xang) or (tu quang)) xa hoi. ((hieu van) or (thien van)) cham soc va hanh hai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tu xang) OR (tu quang)) xa hoi. ((hieu van) OR (thien van)) cham soc va hanh hai cua tu.
• Adding a wildcard symbol may retrieve word variants: toc sach ((tu xang) or (tu quang)) xa hoi. ((hieu van) or (thien van)) cham soc va hanh hai cua tu*.