Perhaps you should try some spelling variations:
hoang van » hang va
thu mach » thu sach, thuat mach, thuc cach
pho hong » pho thong, pho uong, pho dong
hong duc » dang duc, ton duc
ma hoang » mai hoang, m hoang, van hoang
van luan » van quan, van tuan, von luan
mo hoc » mon hoc, co hoc
duc ma » duoc ma, duc mau, duc man

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu mach) or (thu hoach)) hoc tap, nghien cuu mo hoc pho hong duc ma hoang van luan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu mach) OR (thu hoach)) hoc tap, nghien cuu mo hoc pho hong duc ma hoang van luan van.
• Adding a wildcard symbol may retrieve word variants: ((thu mach) or (thu hoach)) hoc tap, nghien cuu mo hoc pho hong duc ma hoang van luan van*.